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Vanessa Richardson
Hi there, it's Vanessa. If you're loving Killer Minds, you won't want to miss my new show, a fellow Crime House Original Conspiracy Theories, Cults and Crimes Every Wednesday, I'll uncover the true stories behind the world's most shocking crimes, deadly ideologies and secret plots. From mass suicides and political assassinations to secret government experiments and UFO cults. Follow Conspiracy Theories, Cults and Crimes now on Apple Podcasts, Spotify, Amazon Music or wherever you listen. And for ad free listening and early access to episodes, subscribe to Crime House plus on Apple Podcasts. This is Crime House. Sibling rivalries can be intense. Especially when one child feels like their parents give their brother or sister preferential treatment. The resentment can get even more intense. When it comes to blended families, the competition gets fierce. One upmanship, small acts of sabotage, maybe the occasional fist fight. But as we get older, those feelings fade away. You might never be best friends, but it's usually easy enough to coexist. That wasn't the case with Nathan Matthews. Even though he was almost 30 years old with a family of his own, Nathan couldn't get over the hatred he felt for his teenage stepsister, Becky Watts. And instead of trying to move past those feelings, he let them consume him until there was nothing left. The human mind is powerful. It shapes how we think, feel, love and hate. But sometimes it drives people to commit the unthinkable. This is Killer Minds, a Crime House original. I'm Vanessa Richardson.
Dr. Tristan Engels
And I'm Dr. Tristan Engels. Every Monday and Thursday we uncover the darkest minds in history. Analyzing what makes a killer Crime House.
Vanessa Richardson
Is made possible by you. Please rate, review and follow Killer Minds to enhance your listening experience with ad. Free early access to each two part series and bonus content. Subscribe to Crime House plus on Apple Podcasts. Before we get started, be advised that this episode contains descriptions of murder, kidnapping and child sex abuse. Material involving teenage girls. Listener discretion is advised. Today we conclude our deep dive on Nathan Matthews, a former British Territorial army veteran who struggled with complicated family dynamics from a young age. As an adult, his self isolation and addiction to violent pornography distorted his reality to the point where he developed a terrifying hatred towards his teenage stepsister. It was a fixation that would ultimately end in tragedy.
Dr. Tristan Engels
As Vanessa goes through the story, I'll be talking about things like a first time killer's mental state as they cover up a crime, how a guilty person can act or react when being questioned, and how a shared obsession between couples can create a shared delusion.
Vanessa Richardson
And as always, we'll be asking the Question what makes a killer?
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Vanessa Richardson
On February 19, 2015, 16 year old Becky Watts was home alone in Bristol, a city in the United Kingdom. It was a Thursday and Becky's dad, Darren Galsworthy, was at work. Meanwhile, her stepmother Angie was at a medical appointment, but Becky wouldn't be by herself for long. At some point that day, after 11am when Angie left for her appointment and well before 12:45pm when she returned home, Becky's stepbrother, 28 year old Nathan Matthews, and his girlfriend, 21 year old Shawna Hoare, arrived at the house. They stopped by a lot, so the fact that they were visiting wasn't unusual. However, the reason for their visit that day was anything but usual. For years, Nathan had resented Becky first for taking all his mother's attention and then for being disrespectful to Angie. Or at least in Nathan's mind she was, to get her to stop. He was planning on teaching Becky a terrifying lesson. When Nathan and Shawna arrived, he was wearing a mask and had a large bag containing handcuffs, a stun gun and tape. For a long time now, he'd fantasized about kidnapping a teenage girl. He'd supposedly decided to indulge that desire by fake kidnapping Becky and scaring her straight in the process. Once Nathan and Shauna were inside, she went out to the garden for a cigarette while Nathan went upstairs to Becky's room. He stormed into find his stepsister, then taped her mouth shut and told her, as long as you do as you're told, you are going to be fine. Nathan took out the handcuffs and clamped them on Becky's wrists. Then he tried to shove her into the bag, but she fought back. The specific sequence of events isn't clear, but during the ensuing scuffle, Nathan punched Becky, causing her to bleed from her mouth. Then he grabbed her throat and utilized a technique he'd learned in military school to restrict blood flow to the head. When he did this, she stopped fighting back, and she also stopped breathing. Becky was dead.
Dr. Tristan Engels
Let's talk about the psychology of someone who goes from fantasy to actualization like this. For individuals like Nathan, the fantasy offers something intoxicating. It's power without consequence. But reality never plays out the way it does in the fantasy. Real people resist or they fight back. They bleed, they cry, or they scream. And for someone whose self worth hinges on control, that resistance can trigger panic or rage or even escalation. Sometimes the individual realizes they're in over their head and they retreat. But others, especially those with poor emotional regulation and a high sense of entitlement, double down. They move from controlled performance to chaotic violence. And that's what we likely saw here with Nathan.
Vanessa Richardson
So siblicide is not something I've heard about often. How common is it? And what are some of the common psychological traits of someone who actually kills a sibling?
Dr. Tristan Engels
Yeah, siblicide, the killing of one sibling by another is rare, but not unheard of. And in terms of statistics, it's estimated to make up around 1 to 3% of all homicides in most countries. So while it's certainly not common, when it does happen, it tends to draw intense attention because it violates such a fundamental social norm, which is the idea. Idea that family, even siblings, are supposed to protect one another, not harm one another like that. So now, when it does occur, we often find a constellation of psychological risk factors in the offender. There isn't a single profile. But patterns do emerge. And as forensic psychologists, we look at patterns. So, for example, chronic resentment is a pattern. Jealousy. A history of parental neglect or inconsistent caregiving. Exposure to violence early on. Personality disorders, emotional dysregulation and family dysfunction are all common patterns. And when we consider that, it's clear that many of these existed in Nathan that went unnoticed.
Vanessa Richardson
Whether or not Nathan intended to kill Becky, once he realized she was dead, he stuffed her body in the bag. Then he brought it out, put it in the trunk of his car, and went back inside to watch TV with Shauna until his mother, Angie returned.
Dr. Tristan Engels
This is evidence of emotional compartmentalization or Callousness.
Vanessa Richardson
Angie came home just before 1pm and although she realized Becky wasn't there, she just assumed her stepdaughter was out with friends. At some point, Becky's boyfriend Luke stopped by to see her, but Shawna told him that she was out. The couple stayed there watching TV and talking with Angie until around 7pm before calling it a night and heading back to their place. It's unclear if Shana knew what was in the trunk of Nathan's car, but he certainly did. And he kept acting like everything was completely normal. When they got home, the couple ordered takeout Chinese food and talked about what to watch on tv. The next day, the couple returned to Darren and Angie's house with their two year old child. It's hard to tell if they went over unannounced or if Angie had called them, but by that point Angie it was clear that Becky was missing. A group of her friends had come over. They hadn't heard from Becky since the day before and they were worried about her. Until that point, Angie had assumed that Becky was out with them. But now nobody had any idea where she was. Shortly after Nathan and Shawna arrived, Becky's dad Darren sped home from work. Once he got there, Darren and one of Becky's friends went upstairs to her room to look for any clues. They quickly realized her phone and laptop were missing, which was alarming. Becky never took her computer out of the house. Darren feared the worst at this point. It was 4pm Nobody had heard from Becky in over 24 hours. He decided it was time to call 999, the UK's equivalent of 91 1. It was all pretty scary, but there was still hope she'd turn up. It wasn't uncommon for teenagers to go missing in the Bristol area and they'd often make it home safe, either found by law enforcement or friends and family. Nathan knew that wasn't going to happen, but he put up a good front. He played the part of the concerned stepbrother to perfection. Before the police arrived, Nathan helped Darren post a picture of Becky on Facebook along with a message that she was missing.
Dr. Tristan Engels
So his post defense behavior is actually common in individuals with narcissistic or antisocial traits. They don't panic in the way a typical person might. Instead, they pivot into damage control, inserting themselves into the search, the narrative, even the center of sympathy. And that's not because they care. It's because it allows them to manage how others see them. Nathan helping his stepfather post on Facebook about Becky's disappearance is a Perfect example of this. It may have served several psychological purposes, like deflection, narrative control, and satisfaction. Because he has sadistic traits, he would feel a perverse sense of power in knowing that he holds the truth while everyone else is scrambling to find it. Nathan's callous post offense behavior also suggests this had nothing to do with feelings of guilt or remorse. But it is possible he felt some level of anxiety about being caught, so he went into performance mode to mitigate any potential consequences.
Vanessa Richardson
Well, for the time being, nobody suspected that Nathan and Shauna had anything to do with Becky's disappearance. And although the police asked them about their activities the day before, it seemed to be in a purely informational capacity. Nathan told them that when he and Shauna came over at some point before 12:45pm they'd heard music in Becky's room. Shauna added that she heard the front door slam shut while she was in the garden, although she never actually saw Becky leave the house. Over the next few days, the police launched their missing persons investigation, and people all over Bristol volunteered to join the search party. The turnout was so large, it seemed like everyone in the city had joined except Nathan and Shauna. Nathan was busy making sure the investigators never found Becky. And Shauna, whose role in the murder was unclear up until this point, was helping him. The day after Becky's murder, likely right after he spoke to the police, Nathan went to a home improvement store and bought a circular power saw, gloves, face masks and goggles. Then two days later, on February 22, he and Shauna bought trash bags, rubble sacks, rubber gloves, bleach, and three rolls of cling wrap. They went to multiple stores to get the rest of their supplies. More tape, sponges, and rubble sacks. Once they had everything they needed, Nathan used the power saw to dismember Becky's body in his bathtub. Shauna was home during this time, and she allegedly assisted Nathan in carefully packing the remains into bags wrapped in cling wrap and tape. One of them even searched on their phone and do you want to hide a dead body? Nathan and possibly Shauna then used the cleaning products they bought and scrubbed down their house, especially their bathtub. Meanwhile, the search for Becky was intensifying, and the public was hard at work, too. A social media campaign started around this time with the hashtag FindBecky. Trending Community search parties continued as well, with impressive turnouts. And while most of the family was constantly at Darren and Angie's house making posters and handing out leaflets, Nathan and Shauna were conspicuously absent.
Dr. Tristan Engels
Okay, so while the rest of the family was in crisis mode. Nathan was trying to do two very contradictory things. He's maintaining the illusion of normalcy and attempting to contain the reality of what he'd done by working hard to cover it up. That kind of duality is incredibly difficult to sustain for most people, But Nathan has been living in that duality for most of his life. Now, overall, his behavior isn't atypical. We see this sometimes in individuals with narcissistic or antisocial traits. They, like I said, lean into rationalization, compartmentalization, and arrogance. And that's what he appears to be doing here, because, again, he's trying to maintain some resemblance of control.
Vanessa Richardson
We've covered serial killers on this show who also dismembered their victims, Like Jeffrey Dahmer, Joel Rifkin. Both of those men were like Nathan in some ways. They were lonely and disconnected from the world. Is it significant that they disposed of their victims in the same way? Is there anything we can learn about Nathan from that?
Dr. Tristan Engels
Yes, it's significant, especially when we consider the underlying psychological motivations. Dismemberment is rarely spontaneous. And while it may serve practical purposes, like concealment or hindering identification of the victim, it often reflects far more than that psychologically. It's frequently associated with individuals who exhibit marked emotional detachment, Fantasy driven control, and a need to dominate or dehumanize the victim. All of which are consistent with Nathan as well as Joel Rifkin and Jeffrey Dahmer. And although Nathan is not a serial killer, he certainly shares traits with them, which means it's highly possible he would have gone on to become one if he hadn't been caught.
Vanessa Richardson
Well, for the time being, the police were still buying Nathan's act. And on February 24, four days after Becky was reported missing, he gathered the neatly packaged bags that contained her remains and brought them to a friend's shed. This friend lived very close by, Just a few hundred feet from Nathan's house. There, allegedly unbeknownst to the friend, Nathan hid all the evidence from his crime. But he didn't realize he'd left something behind on the day of the murder. And after multiple searches of Becky's house, the forensics team finally found it outside Becky's bedroom. On her door frame were three tiny smears of blood, along with a clear outline of a fingerprint.
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Vanessa Richardson
Sometime during the week after Becky Watts disappeared in February 2015, forensic investigators found a bloody fingerprint on her bedroom door frame. This was a huge breakthrough for two reasons. One, it was a huge piece of forensic evidence that they could test against future suspects. And two, the blood indicated that Becky had been injured and forcibly removed from her home, which allowed detectives to broaden their investigation. Because now they weren't just looking for a missing person. They were looking for a kidnapping victim. After this discovery, more law enforcement jurisdictions were brought in to assist the Bristol police. More manpower meant more scrutiny. And the first order of business was to re interview Becky's family. And this time, Nathan was much less cooperative. He kept making excuses about why he couldn't come in, which raised the investigators suspicions. But when he did eventually sit down with them, he was surprisingly calm and relaxed. Approachable even. Nathan even laughed and joked with the officer conducting the interview.
Dr. Tristan Engels
Nathan's demeanor during the second interview was noteworthy because he was unexpectedly calm, even lighthearted. But now it's important to clarify. Behavior alone doesn't determine guilt or innocence. People respond to high stress situations in a wide range of ways. Some innocent individuals shut down or seem evasive. Some guilty individuals appear composed. There's no universal blueprint for how someone should act during an investigation. That said, in a forensic context, Nathan's behavior did raise questions. His earlier reluctance to come in, like repeatedly avoiding contact with the investigators, followed by a sudden display of ease once in the interview room, is a pattern that does suggest possible impression management. Investigators are trained to note these shifts because they can speak to how an individual is navigating pressure, not just whether they're feeling it. With that in mind, his calm, joking demeanor could reflect several things. It might indicate emotional detachment or an ability to compartmentalize stress. It could also suggest a strategic attempt to appear cooperative and non threatening, which is a behavior we sometimes see in individuals who want to control the tone of the conversation. In certain cases, it can Align with traits like narcissism or with superficial charm, Especially if the person believes they can steer perception or outmaneuver the suspicion of investigators. So while Nathan's behavior in the room Wasn't inherently incriminating, it stood out not because he was calm, but because of the contrast between that composure and his earlier avoidance, and because of what it might suggest about how he relates to stress, scrutiny, and control in high stakes situations.
Vanessa Richardson
Nathan wasn't the only one keeping his composure. When Shauna was questioned, Investigators found that she was cool, calm, and collected as well. But there was one thing that bothered them. Nathan and shauna's versions of what happened that day Were so identical, it seemed coordinated. The authorities were still waiting for some forensic tests to come through. The blood from Becky's bedroom door frame, along with the fingerprint, Were still being analyzed. But given Nathan's nonchalant attitude during questioning and his possible collusion with shauna over their stories, Investigators were getting suspicious. So a few days later, Just before the end of February, Nathan was called back to the station for more questioning. He still came off as cooperative and relaxed, but at some point during the interview, he let something slip. He told the police he didn't like Becky and he resented how she treated his mom. He said it so matter of factly that it's unclear if he was even aware of how important this was to the investigation.
Dr. Tristan Engels
So first, that could very well have been a subconscious slip. In investigation interviews, especially after repeated questioning, People sometimes reveal underlying emotions or beliefs without realizing how significant that disclosure is. In Nathan's case, he may have become desensitized to the weight of what he was saying. Like it no longer felt like a confession. Rather, it felt like a truth he had told himself so many times that it no longer registered as incriminating to him. That said, there's also another possibility. This could have been a calculated attempt at a partial disclosure, Like a way of releasing controlled information to investigators. By giving a selective truth, he may have done this to appear honest. It's also possible that Nathan made the submission out of a sense of confidence or perceived rapport, Believing he'd established a friendly dynamic with the investigators. After several interactions, Interviewers often adopt a non confrontational, conversational approach to encourage disclosure. And individuals in Nathan's position May interpret that tone as genuine camaraderie, which could lead them to reveal more than they intend to. Whatever the reason, this kind of admission is actually very relevant to an investigation because it could establish a motive.
Vanessa Richardson
Whatever Nathan's reasons were for telling the police, how he felt about Becky. He essentially handed them a motive on a silver platter. After that interview, they started looking at Nathan as the primary suspect, with Shawna as a possible accomplice. They seem to already have at least Nathan's fingerprints on file, likely taken at some point during one of his interviews. So at this point, they were just waiting for the forensics to come back and confirm their suspicions. Soon, they got their wish. The results confirmed that the bloody fingerprint was indeed Nathan's, and the blood it had been smudged in was Becky's. On February 28, the police arrived at Nathan and Shawna's home and placed them both under arrest for kidnapping. It had been eight days since Becky was reported missing, and the authorities were still hoping she was alive. Once the couple was brought back to the station, they were questioned separately. They knew Shauna was more articulate than Nathan, and their approach with her was to keep her talking as much as possible. They hoped she'd eventually reveal a clue that led to Becky's whereabouts. But she didn't. She just said Nathan had nothing to do with it. When it came to Nathan, the detectives tried a different tactic. They knew from questioning him earlier that he liked to feel in control. So in order to take the power out of his hands, they made sure he knew that they had evidence against him. Meanwhile, police teams combed over Nathan and Shauna's house to look for signs of where they were keeping Becky. As soon as the investigators entered the home, they could see how filthy it was. Like a porter's, almost. But when they got to the upstairs bathroom, they noticed something odd. The bathtub was incredibly clean. It was an anomaly in an otherwise unlivable house. And when they scoured the rest of the place for more evidence, they found a pile of it in the attic crawl space, a wad of receipts for the circular saw, and the other supplies Nathan bought to dispose of Becky's body. When detectives looked at those receipts and saw what Nathan had purchased, they knew this was no longer a kidnapping. It was a murder investigation. The authorities went back to the station, and the detectives then presented this evidence to Nathan. That's when he realized he was caught. On March 2, 2015, through a prepared statement by his lawyer, Nathan admitted to murdering his stepsister, Becky Watts. However, he claimed he hadn't planned to kill her. Nathan said it happened in a moment of panic. His mask slipped and Becky saw his face. So he just instinctively reacted. When asked about Shauna's role in Becky's death, Nathan said she didn't have anything to do with it. According to him, Shauna didn't even know about it.
Dr. Tristan Engels
It's not entirely unexpected or even uncommon that Nathan confessed. Individuals confess for a variety of reasons, and it's rarely out of guilt or remorse. In cases like this, a confession may reflect a strategic response to overwhelming evidence. So for example, when a suspect perceives that there is no viable path to continuing, denying it or escaping it, they may choose to confess in order to regain a sense of control, minimize the consequences, or in some cases, protect someone else. In Nathan's case, I think it was to regain control, protect his image, and it was self serving.
Vanessa Richardson
Well, it really seemed like the dam had burst because during Nathan's confession, he also gave detectives the piece of information they wanted the most. Where Becky was. Investigators then went to the shed where Nathan had hidden everything. The sight of Becky's remains meticulously wrapped in plastic bags was horrific. But as gruesome as it was, it also gave the authorities hope. Because in that shed, they had everything they needed to hold Nathan Matthews accountable for his crimes.
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Vanessa Richardson
On March 2, 2015, 28 year old Nathan Matthews admitted to killing and dismembering his 16 year old stent stepsister, Becky Watts. When news of his arrest got back to their family, there were A few different reactions. No one knew about Nathan's confession yet, so Nathan's stepdad, Becky's father, Darren, actually thought investigators had it wrong. They didn't. But there was still a long way to go before Nathan was brought to justice. In particular, authorities wanted to know if he was lying about Shauna's involvement.
Dr. Tristan Engels
So, objectively, it's not uncommon. But it is notable that Nathan did not attempt to deflect blame onto Shauna when he confessed. Given his treatment of Shauna and his pattern of callousness, even I actually expected him to implicate her in order to save himself. But the reality is, in some cases, suspects in relationships where there's intimate partner violence engage in protective behavior, especially if they view their partner as dependent or subordinate or they had some kind kind of investment in the relationship that they want to preserve. In Nathan's case, I'm inclined to believe that it's calculated self interest. As long as Shawna serves some kind of function for him, he wants to maintain control of her. And keeping her safe from prosecution, in his mind, means he maintains her support in different ways. And he will need that support where he knows he's likely headed.
Vanessa Richardson
That is so fascinating. What does it say about Nathan that he was able to bother, harm and protect?
Dr. Tristan Engels
So that once again, speaks to his capacity to compartmentalize not just emotions, but even morality, but also his continued need for control. Control of image, the narrative, his relationship, and the investigation. It's certainly possible, too, that he had a genuine attachment to Shawna. There was, at a minimum, a trauma bond between them. But as the abuser, they often equate ownership with loyalty. So showing his devotion and loyalty allows him to maintain his sen of ownership and control. And like I mentioned previously, when it comes to individuals like Nathan, their actions are often selective and self serving. On the outside, it may appear like he's experiencing love or remorse, even protectiveness. But in truth, it's all for his own self interest. Protecting Shauna means outside support. It means financial support, emotional support, and psychological support. He's losing control over everything, especially when he goes to prison. So right now, the last thing he has control over that he's maintaining is Shauna. So someone like Nathan will want to maintain that however he can. And we've seen how. What lengths he will go to in order to keep that control.
Vanessa Richardson
On March 3, one day after Nathan's confession, Shauna was questioned again. She maintained her innocence. She said she hadn't known what Nathan did until his confession the day before. But the authorities weren't Convinced, they searched the couple's phones and computers and found the violent text they shared, along with the child sex abuse videos they watched. After the computer SEIZURE and almost 100 hours of questioning, Nathan was officially charged with murder and put into custody. Shauna was charged a few weeks later when they connected her DNA found on the face masks and bags that were taken from the shed where Becky's body parts were found. Nathan and Shauna went on trial together about seven months later in October 2015. The evidence was hard to stomach, along with having to confront the devastating state Becky's body was found in. The jury also heard detailed analysis on what could have driven Nathan and Shauna to pull off such a heinous crime. Much of Shauna's portion of the trial was dedicated to her being an abuse victim, controlled by Nathan's physical and psychological torment. But David Wilson, a professor of criminology at Birmingham City University, thought there was something else at play with the couple. He suggested that Nathan and Shauna suffered from a form of shared madness called foliadu.
Dr. Tristan Engels
So, yeah, let's talk about folie a deux. That's a term I haven't heard in a long time, and it's a French term that stands for, like you mentioned, madness of two. Clinically, it refers to a very rare psychiatric syndrome where two or more people share the same delusional beliefs. Beliefs typically within a close, isolated relationship, such as between romantic partners, siblings, a parent and a child. It's also known as shared psychotic disorder or shared delusional disorder. In the psychiatric realm, I've always known it to be referred to as shared psychosis. While foliadu is rare, it highlights how dysfunctional dynamics and psychological dependency can distort reality, especially when one person has an influential or coercive role. It's most relevant in forensic settings when trying to understand understand co offender dynamics or cases where one partner seems to participate in harmful behavior under the influence of another's delusional or dominant thinking. That being said, it's no longer in the Diagnostic and Statistical Manual of Mental Disorders as a standalone diagnosis. It was removed in 2013 and folded into broader categories of psychotic disorders. I understand why this comparison was proposed. The dynamics between them definitely bear the resemblance there, but they did not appear to meet the full criteria. From what we know here, Obviously, I've never evaluated them, so I'm not saying with full certainty. But from what we've outlined, there doesn't seem to be clear evidence that Nathan held a primary delusional belief or that Shawna Adopted it. Simply being fixated on Becky or displacing anger onto her because of jealousy or unprocessed rage does not necessarily rise to the level of a clinical delusion. Based on that information, we have what this reflects more accurately in my view, again based on what we know, and something I've seen frequently when evaluating women who are co defenders in a case with their male partners is their behavior is often driven by the need to appease their dominant partner. This stems from a combination of factors like fear, psychological dependency, coercion, isolation, trauma bonding, and sometimes substance abuse. That's very different from shared delusions or psychosis. Coercive control can gradually diminish a person's autonomy over time, creating a sense of emotional captivity where the victim becomes increasingly compliant, disoriented even, and are unable to set boundaries and unable to do so safely. And we cannot overlook that Shawna was still a child when she met Nathan. That early exposure means there was grooming involved, which most certainly set the stage for long term and total control, especially now that they have a child that Shauna was likely also wanting to protect. So now I say all that to provide context to help understand co offender dynamics, not to minimize Shauna's culpability. Because at this point, Shawna is an adult and from what we know is of sound and rational mind. She knows right from wrong and she could have found safe ways to leave this abusive situation to protect her and her child. Nathan's mother is an example that that is possible.
Vanessa Richardson
It was certainly an interesting argument. And when the five week trial ended, the jury deliberated for three hours and 27 minutes before finding Nathan guilty of murder. Shauna was convicted of manslaughter. When the verdicts were read, there were audible gasps of relief from the people in the courtroom. Nathan bowed his head while Shauna just stared into space, wiping tears from her eyes. Nathan was sentenced to life in prison with a minimum sentence of 33 years. Shauna got 17 years. Some believe the punishments were far too generous, at least when it came to Nathan. Darren, Becky's dad, thought his stepson, who was the best man at his wedding, deserved the death penalty. But that didn't mean Darren abandoned Nathan's mother. He and Angie stayed married and supported each other through this turmoil. But Angie did have have a long road ahead of her. She had to reckon with loving her son while also accepting what he'd done. Which seems like an impossible thing to process because what Nathan did feels so inexplicable. Both Becky and Nathan were raised in similar circumstances. They had to contend with being raised in a blended family and struggled to connect with others, but while Becky rose above it. But Nathan let his troubles consume him and as a result, he destroyed both of their lives. Thanks so much for listening. Come back next time. Time for a deep dive into the mind of another murderer.
Dr. Tristan Engels
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Vanessa Richardson
To enhance your listening experience, subscribe to Crime House plus on Apple Podcasts. You'll get every episode of Killer Minds ad free along with early access to each thrilling two part series and exciting bonus content. Killer Minds is hosted by me, Vanessa Richardson and Dr. Tristan Engels and is a Crime House original powered by Pave Studios. This episode was brought to life by the Killer Minds team. Max Cutler, Ron Shapiro, Alex Benedon, La, Lori Marinelli, Natalie Pertzofsky, Sarah Camp, Kate Murdoch, Seth Blerger, Leah Roesch and Keri Murphy. Thank you for listening. If you love Killer Minds, tune into the Crime House original Conspiracy Cults and Crimes for the world's darkest truths. Follow Conspiracy Theories, Cults and Crimes now wherever you get your podcasts and for ad free listening and early access to episodes, subscribe to Crime House plus on Apple Podcasts.
Episode: MURDEROUS MINDS: The Killer Step-Brother Pt. 2
Release Date: August 21, 2025
Hosts: Vanessa Richardson & Dr. Tristan Engels
This gripping episode concludes the harrowing two-part exploration into the case of Nathan Matthews, a British Army veteran whose hatred for his teenage stepsister, Becky Watts, escalated into kidnapping, murder, and dismemberment. Hosts Vanessa Richardson and forensic psychologist Dr. Tristan Engels weave together detailed crime storytelling and psychological analysis to examine how complex family dynamics, unresolved resentments, and psychological dysfunctions culminated in a shocking domestic tragedy.
Becky Watts' Disappearance (04:53)
Crime Committed (06:00)
“He stormed in to find his stepsister, then taped her mouth shut...The specific sequence of events isn't clear, but during the ensuing scuffle, Nathan punched Becky...then grabbed her throat and utilized a technique he'd learned in military school to restrict blood flow to the head. When he did this, she stopped fighting back, and she also stopped breathing. Becky was dead.”
— Vanessa Richardson (06:41)
“For individuals like Nathan, the fantasy offers something intoxicating. It's power without consequence. But reality never plays out the way it does in the fantasy...”
— Dr. Tristan Engels (07:25)
“Nathan helping his stepfather post on Facebook about Becky's disappearance is a perfect example...it allows them to manage how others see them...he would feel a perverse sense of power in knowing he holds the truth.”
— Dr. Tristan Engels (11:51)
“Their behavior isn't atypical...They lean into rationalization, compartmentalization, and arrogance, trying to maintain some resemblance of control.”
— Dr. Tristan Engels (15:20)
Turning Points
Interrogation Techniques and Confession (20:12 – 24:15)
“His calm, joking demeanor could reflect several things...emotional detachment, ability to compartmentalize stress, or a strategic attempt to appear cooperative.”
— Dr. Tristan Engels (20:12)
“People sometimes reveal underlying emotions or beliefs without realizing how significant that disclosure is. In Nathan's case, he may have become desensitized to the weight of what he was saying.”
— Dr. Tristan Engels (22:58)
Evidence and Arrests (24:15 – 27:17)
Confession and Motive (27:17 – 27:55)
“A confession may reflect a strategic response to overwhelming evidence...in order to regain a sense of control, minimize the consequences, or protect someone else.”
— Dr. Tristan Engels (27:17)
“What this reflects more accurately...is behavior often driven by the need to appease their dominant partner...This stems from fear, psychological dependency, coercion, isolation, trauma bonding...”
— Dr. Tristan Engels (34:23)
On Post-Offense Behavior:
“Nathan has been living in that duality for most of his life.”
— Dr. Tristan Engels (15:20)
On Compartmentalization:
“That once again, speaks to his capacity to compartmentalize not just emotions, but even morality, but also his continued need for control.”
— Dr. Tristan Engels (31:41)
On the Outcome:
“Both Becky and Nathan were raised in similar circumstances...but Becky rose above it. Nathan let his troubles consume him and as a result, he destroyed both of their lives.”
— Vanessa Richardson (37:34)
| Timestamp | Segment Description | |-----------|-------------------------------------------------------------| | 04:53 | Details of the crime and Becky's death | | 07:17 | Analysis of fantasy-driven violence | | 08:11 | Psychology of siblicide | | 09:16 | Cover-up and post-crime family interactions | | 11:51 | Analysis of Nathan’s social media behavior | | 12:51 | Purchasing and use of dismemberment tools | | 15:20 | Psychology of offenders covering up crimes | | 19:00 | Discovery of forensic evidence (bloody fingerprint) | | 20:12 | Nathan's interview demeanor | | 22:58 | Subconscious slips and establishment of motive | | 24:15 | Shift from missing persons to murder investigation | | 27:17 | Confession and reasons behind it | | 34:23 | Folie à deux and co-offender psychological dynamics | | 37:34 | Trial verdicts, sentencing, and family aftermath |
The episode ends with a reminder of the devastating consequences of unchecked hatred and dysfunctional family dynamics. Despite similar life circumstances, Becky overcame her challenges while Nathan allowed his to manifest violently, destroying two lives and leaving deep scars on their family.
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