Podcast Summary: 20/20 True Crime Vault – “The Devil’s Triangle”
Podcast: 20/20
Host: ABC News
Episode: True Crime Vault: The Devil's Triangle
Date: August 26, 2025
Overview
This gripping episode of 20/20 True Crime Vault unpacks the disappearance of 20-year-old Heather Elvis from Horry County, South Carolina. Her case—one of love, obsession, and betrayal—unfolds against the seemingly idyllic backdrop of Myrtle Beach. The episode dives deep into the tangled relationships that led to her vanishing, the exhaustive investigation, and the sensational trials of Sidney and Tammy Moore, leaving listeners with haunting questions about justice and closure.
Key Discussion Points and Insights
1. Heather Elvis’s Life and Disappearance
- Heather’s Background: Described as a vivacious, creative free spirit with ambitions in fashion and media.
- “She always wanted to live life to the fullest. ...She didn't understand boundaries when it came to dreaming.” (Narrator/Host, 04:11)
- Night of Disappearance (Dec 18, 2013):
- Heather went on a date with Steven Schiraldi, learned stick shift, shared joyful texts and selfies with her mom (11:00–12:10).
- Later, her car was found abandoned at Peachtree Boat Landing—an ominous, isolated location. Her possessions were inside, but she was gone.
- “There is no reason for a car to be there abandoned in the middle of the night.” (Narrator/Commentator, 01:17)
- Heather’s family becomes frantic, noting her phone going straight to voicemail—very out of character (08:23).
2. The Secret Affair and the Triangle
- Heather’s New Love: Initially, everyone thought Steven was the main person in her life—but coworkers point investigators to another man: Sidney Moorer (13:17).
- Heather & Sidney’s Affair:
- Sidney (37, married, three children) was a night maintenance man at Heather’s workplace, the Tilted Kilt.
- Their relationship was passionate—and an “open secret.”
- “Sydney and Heather were having sex all the time, anywhere that they could.” (Prosecutor/Legal Expert, 14:07)
- Obsession and Tensions:
- Sidney’s wife, Tammy Moore, discovers the affair and becomes enraged, subjecting Heather to persistent threats and harassment, including repeated calls, texts, and explicit videos (21:17–22:18).
- “Hey sweetie, you ready to meet the Mrs.?” (Tammy to Heather, via Narrator/Host, 21:34)
- Both Heather and those around her sense real danger—her demeanor becomes fearful and paranoid (22:55).
3. Escalation and Threats
- The Moore Marriage: Tammy emerges as controlling; after previous infidelities, she exerts dominance over Sidney—chains him to bed, closely monitors his contacts, and forces a tattoo of her name on him (54:19).
- A Nasty Breakup:
- After the affair’s exposure, Sidney distances himself from Heather and publically humiliates her in a call (“…you were just some girl that spread your legs.” [21:01])
- Heather is heartbroken, frightened, but begins moving on, even seeing Steven on the night she disappeared (24:57).
4. The Payphone, The Timeline, and Early Suspicions
- Payphone Clue: Police quickly hone in on a string of early morning calls between Heather and a payphone (27:41).
- Surveillance shows Sidney at the payphone; he denies involvement but is later contradicted by evidence and testimony (28:09–29:39).
- Heather’s roommate recounts a 1:44am call where Heather claims Sidney begged to reunite and said he’d left his wife (30:00).
5. Evidence Mounts Against the Moores
- Tracking Movements: Phone and surveillance records place both Sidney and Tammy near Peachtree Landing during Heather’s disappearance window. Their black Ford F150 matches a vehicle seen coming and going from the area (33:39–35:27).
- Manipulating Evidence: The GPS in their truck was removed only on the night Heather vanished. Their home’s security system was conveniently replaced right after the events (36:45–37:33).
- Burning and Cleaning: Surveillance shows Sidney and Tammy meticulously cleaning and burning evidence from the truck (74:18–75:15).
6. The Trials and Legal Drama
- Circumstantial but Compelling: Despite lacking physical evidence or Heather’s body, prosecutors build a narrative based on circumstantial evidence, focusing on motive (possible pregnancy) and behavioral patterns (40:57–44:14).
- First Trial (Sidney): Ends in a mistrial (47:23), but Sidney is later convicted of obstruction of justice (48:42).
- Tammy’s Trial:
- Prosecution highlights her domineering behavior and relentless pursuit of Heather.
- “She even chains him to the bed at night. I’m not speaking figuratively to you right now. Literally chains him to the bed at night.” (Narrator/Investigator, 54:19)
- Tammy testifies, remaining combative and denying all accusations. Deliberations yield a swift guilty verdict: 30 years in prison for conspiracy to kidnap and kidnapping (68:29–69:10).
- Sidney’s Retrial:
- Fresh evidence (surveillance video of cleaning/burning, witness testimony from Tammy’s cousin) tips the jury, leading to another 30-year sentence (80:08–80:33).
Notable Quotes and Memorable Moments
- On Myrtle Beach’s Dark Underbelly:
- “In these swamps, anything can happen, anything can disappear. Even a body.” (Narrator/Commentator, 01:45)
- On Loving and Losing Heather:
- “We miss you, but we want you home. Tell me where you’re at.” (Debbie Elvis, 25:47)
- On Social Media’s Role:
- “It was a social media war, a campaign of pure terror.” (Debbie Elvis, 32:33)
- “Probably the first case where social media took on a life of its own.” (Narrator/Commentator, 38:47)
- On Tammy’s Domination:
- “She has this way of being very, very intimidating. …I’m still thinking about it to this day.” (Witness/Testifier, 54:00)
- “She even chains him to the bed at night. …Literally chains him to the bed at night.” (Narrator/Investigator, 54:19)
- On Heather’s Fate:
- “I hold out hope that I'll turn around one day and she'll walk in. Do I really think that'll happen deep down? No, I don't. …I'll never give up.” (Debbie Elvis, 82:29)
- On Justice and Closure:
- “The perfect solution would be to find Heather Elvis alive, but I don't believe that'll ever happen.” (Narrator/Investigator, 80:56)
Important Timestamps
| Timestamp | Segment Description | |-------------|------------------------------------------------------------| | 04:28–05:43 | Heather’s character, work at Tilted Kilt, her free spirit | | 13:17–14:51 | Introduction of Sidney Moore and the start of their affair | | 21:17–22:18 | Tammy’s threats escalate; explicit calls/texts | | 24:57 | Heather moving on; last night out with Steven | | 27:41–28:09 | Discovery of payphone calls, surveillance clues | | 33:39–36:10 | Surveillance: truck movements, cell phone, GPS removed | | 41:39–44:28 | Theories: Pregnancy motive, circumstantial case | | 47:23 | Sidney’s first trial ends in mistrial | | 48:42–49:03 | Sidney convicted of obstruction of justice | | 68:29–69:10 | Tammy Moore convicted, sentenced to 30 years | | 80:08–80:33 | Sidney Moore convicted, also sentenced to 30 years | | 82:29 | Debbie Elvis’ heartbreaking hope for closure |
Conclusion
The Devil’s Triangle delivers a tragic exploration of a small-town mystery consumed by obsession, rage, and the search for justice. It’s a cautionary tale about the dark side of passionate relationships, the corrosive potential of jealousy, and the relentless demand for answers from those left behind. The episode’s original voices—painful, candid, and at times poetic—reveal the human cost of violence and uncertainty.
Heather Elvis’s body was never found, but the episode closes with her family’s tenacious hope for truth, a town forever changed, and a warning about the profound consequences of secrets kept in the shadows.