Cold Case Files

Episode: "A Deadly Affair / The Sting Operation"

Release Date: March 31, 2026
Host/Narrator: Marisa Pinson
Podcast Network: A&E / PodcastOne

Episode Overview

In this gripping episode, Cold Case Files investigates two chilling cold cases that were ultimately solved decades after the crimes took place. The first half of the episode, "A Deadly Affair," recounts the 1982 murder of David Harmon in Olathe, Kansas—an apparent home invasion that, upon reinvestigation, reveals the dark undercurrents of a love triangle and a staged crime scene. The second story, "The Sting Operation," shifts focus to the 1977 murder of Officer Abe Pipkin in Beebe, Arkansas, and details the elaborate undercover operation that finally brought his killer to justice after a quarter-century of speculation.

Case 1: A Deadly Affair (David Harmon Murder, Kansas, 1982)

Case Introduction & The Crime Scene

• [00:34] Narrator: Cold case detectives Bill Wall and Steve James reopen the 1982 unsolved murder of David Harmon, a bank teller found beaten to death in his home.
• [00:45] Det. Bill Wall: The crime scene lacked typical signs of a break-in or robbery.
  "It doesn't look to you as being anything even close resembling a robbery or a home invasion." ([00:45])
• Initial police efforts focus on Melinda Harmon’s (the widow) home invasion account.

Immediate Suspicions & Shifting Stories

• [01:50] Gail Bergstrand (Neighbor): Recalls Melinda’s ambiguity and uncertainty about David's fate.
  "She said, 'I think Dave is dead. I think Dave could be dead.'" ([01:50])
• [03:01] Officer J.W. Larich: Melinda claims thugs broke in searching for bank keys, assaulted her, and left her husband fatally injured.
• [04:00] Det. Joe Pruitt: Melinda described her assailants as "probably black males" based on voice alone—details that later prove questionable.
  "This bruise on her left cheek was about the size of a dime...She was able to answer our questions. She was not overly upset." ([04:00])

Doubting the Home Invasion Story

• [04:37] Det. Joe Pruitt: Questions the logic of stealing bank keys that are useless due to a time lock.
  "What would anybody accomplish by taking the keys and breaking into the bank in the middle of the night?" ([04:37])
• [05:25] Paul Morrison (Prosecutor): The implausibility of Melinda’s story becomes obvious as no attempted bank robbery occurs.

Emergence of a Suspect: Mark Mangelsdorf

• [05:47] Det. Joe Pruitt: Mark Mangelsdorf, a college student and family friend, found at the scene with wet hair—arousing suspicion due to the unusual timing.
  "It was wet, like he had taken a shower." ([05:47])
• [06:16] Det. Joe Pruitt: Letters between Melinda and Mark suggest a romantic relationship, establishing a possible motive.

Quote:

• "Some of those were signed 'Love, Melinda.' They were very personal, more so than what you would think of friends." ([06:16])

Case Goes Cold

• Family closes ranks around Melinda; she is taken out of state, and the investigation stalls due to lack of hard evidence.
• [07:22] Det. Joe Pruitt:
  "We thought from the very beginning that there was enough information to arrest both of them for David’s murder. But we never thought for one minute there was enough information to convict them."

Reopening the Case (2001) & Forensic Breakthroughs

• [07:49] Det. Bill Wall: Cold case detectives revisit evidence in 2001.
• Analysis of Melinda's nightgown reveals only minor blood on the lower portion—contradicting her “violent struggle” story.
  • "She should have had a lot more blood on. This nightgown just reaffirmed everything..." ([08:47])

Confronting the Widow

• Detectives travel to Ohio to question Melinda (now Melinda Rash).
• She changes her story significantly, telling detectives there was only one masked intruder (not two), then tries to downplay her relationship with Mark.
• [11:09] Melinda Rash: When pressed on why she invented parts of her initial story:
  "At the time, I didn’t know it was a story."

Turning on her Co-conspirator

• [12:39] Melinda Rash: Admits suspecting Mark in her heart, but hedges full admission.
  "In my heart, I knew it was him."
• [13:05] Melinda Rash: Stops short of confessing to a murder plot.

Deal-Making & Legal Wrangling

• Melinda negotiates with prosecutors, implicating Mark for a plea deal.
• [14:30] Paul Morrison:
  "Innocent people don't negotiate deals. And that kind of stuff just kills you."

The Prosecutions

• Both are indicted for murder. Mark refuses to talk. Melinda’s interrogation tape is played at trial.
• Mark takes the stand and repeatedly denies a romantic relationship.
  • [17:34] Mark Mangelsdorf:
    "I was not in love with Melinda Harmon. I did not have a romantic or sexual or physical relationship..."
• Prosecutor Morrison needles Mark for not coming clean.
  • [18:34] Morrison:
    "What's the word for someone who doesn't tell the truth? ... It starts with an L." (trying to get Mark to say "liar")

Verdicts and Sentencing

• [19:52] Jury:
  "On count one, we, the jury, find the defendant guilty of murder. On count two, guilty of conspiracy to commit murder."
• Melinda’s convictions are set aside for her testimony; she pleads to second-degree murder, and then Mark also pleads guilty to second-degree murder ([21:04-21:21]).

Powerful Moment

• [22:00] John Harmon (victim’s father): Addresses his son’s killers in court:
  "You took our one and only child in a vicious act of violence. ... What a waste. What a complete waste of a human life."
• [22:45] Mark Mangelsdorf: Apologizes for his role:
  "Mr. Harmon, I can't begin to imagine the grief ... I have tried to do the right things throughout my life and especially for the last 24 years. And that's genuine."
• Both are sentenced to 10–20 years.

Case 2: The Sting Operation (Officer Abe Pipkin, Arkansas, 1977)

Revisiting an Officer’s Murder

• [25:27] Narrator: On April 5, 1977, 71-year-old Officer Abe Pipkin is killed during a pharmacy burglary in Beebe, Arkansas.
• [26:29] Joe Pipkin (son):
  "It just didn't happen. In a small town, you know, something like that just didn't happen."
• Initial investigation yields no witnesses or viable suspects; case goes cold ([27:11]).

False Confessions and Dead Ends

• Years later, infamous serial killer Henry Lee Lucas confesses, but evidence places him in Maryland at the time of the crime ([29:18]).

A New Lead Decades Later

• [30:01] Harold Armstrong (Police Chief): Receives a call from an informant implicating a woman named Mitzi Pardue, who had inside knowledge about the murder from her then-boyfriend, Gary Evans.
• [30:48] Mitzi Pardue:
  "When they asked me to come down to the sheriff's office, I pretty much knew what it was for."
• Mitzi recounts Gary’s confession after the crime.

The Sting – Nine Years in the Making

• Police ask Mitzi to wear a wire and confront Gary Evans, but she’s too fearful at first.
• After nearly a decade, Mitzi is finally ready to cooperate; she has moved on, is married, and more confident ([36:03]).

Quote:

• [36:18] Captain J.R. Howard:
  "Her life had changed. She was married, had a good husband, kids, and she was ready to help us out."

Executing the Operation

• Mitzi’s car is wired; she visits Gary at his workplace ([38:33]).
• During a casual drive and conversation, Gary admits to the killing, though he's hesitant at first.
  • [41:41] Gary Evans (to Mitzi):
    "I just can't believe I did it either. I pulled and I hit him with a crowbar, you see?"

Quote:

• [43:59] Prosecutor Chris Raff:
  "Without that tape and without Mitzi, we would not have had one thing. That was the case against Gary Evans."

Trial & Conviction

• The jury is shown the undercover video; Gary Evans is convicted of first-degree murder and sentenced to 30 years ([44:27]).
• [45:21] Joe Pipkin:
  "And I prayed that we would find him and justice would be served. And it was. God answers prayers–may take a while."

Memorable Quotes & Timestamps

• "This was a crime. When you just look at strictly the picture, it doesn't look to you as being anything even closer resembling a robbery or a home invasion."
  – Detective Bill Wall ([00:45])
• "The real thing that stuck in our mind was what would anybody accomplish by taking the keys and breaking into the bank in the middle of the night...?"
  – Detective Joe Pruitt ([04:37])
• "In my heart, I knew it was him."
  – Melinda Rash (Harmon) ([12:39])
• "Innocent people don't negotiate deals. And that kind of stuff just kills you."
  – Prosecutor Paul Morrison ([14:30])
• "I was not in love with Melinda Harmon. I did not have a romantic or sexual or physical relationship with her."
  – Mark Mangelsdorf ([17:34])
• "You took our one and only child in a vicious act of violence...What a waste. What a complete waste of a human life."
  – John Harmon ([22:00])
• "Without that tape and without Mitzi, we would not have had one thing. That was the case against Gary Evans."
  – Prosecutor Chris Raff ([43:59])
• "And I prayed that we would find him and justice would be served. And it was. God answers prayers–may take a while."
  – Joe Pipkin ([45:21])

Key Insights & Takeaways

• Forensic Consistency: Persistent reexamination, careful forensic analysis (like the blood pattern on Melinda's nightgown), and advances in investigative techniques can turn a cold case around even after decades of dormancy.
• Change in Testimony as Evidence: Shifting stories and admissions—even if partial—played as pivotal a role as physical evidence.
• Role of Relationships: Both cases were ultimately solved thanks to personal connections (affair in Kansas, old relationship in Arkansas) and the willingness of individuals to come forward.
• Complexities of Justice: Deals with co-conspirators, plea bargains, and reluctant witnesses underscore the challenges of securing convictions in cold cases.
• Emotional Weight: The episode ends with powerful family statements at sentencing, underscoring the heavy, ongoing impact of murder on victims' loved ones.

Segment Timestamps for Reference

• David Harmon Murder Case: [00:34–24:17]
• Officer Abe Pipkin Murder Case: [25:17–45:21]

For listeners interested in the details of cold case investigation, police procedure, and the human stories behind decades-long searches for justice, this episode provides compelling, at times harrowing, insight directly from those who lived it.