CSI Sheryl McCollum welcomes back Dr. Katherine Ramsland and Tracy Ullman to discuss their documentary, The Serial Killer’s Apprentice.

This two-hour film reexamines the haunting case of Elmer Wayne Henley Jr. and Dean Corll, integrating archival footage, exclusive interviews, and rare audio recordings.

Dr. Ramsland and Ullman provide behind-the-scenes insights into the documentary’s production. They discuss what has emerged since the book’s publication and why this case, rooted in grooming, complicity, and trafficking, continues to impart important lessons today.

About the Host

Sheryl “Mac” McCollum is an Emmy Award-winning CSI, a writer for CrimeOnline, an expert in forensic science for Crime Stories with Nancy Grace, and co-author of the textbook Cold Case: Pathways to Justice.

She founded and directs the Cold Case Investigative Research Institute, a nationwide collaboration that enhances techniques for solving cold cases and supports families and law enforcement with unsolved homicides, missing persons, and kidnappings.

About the Guests

Dr. Katherine Ramsland is a professor of forensic psychology at DeSales University and the author of numerous books and articles. Her works include

• “How to Catch a Killer”
• “The Mind of a Murderer”
• “The Serial Killer’s Apprentice”

She frequently contributes to crime documentaries and television shows, offering her expertise on serial killers, criminal behavior, and the psychology of predators.

Tracy Ullman is a writer, producer, and investigative journalist who specializes in true crime storytelling and victim advocacy. She co-authored “The Serial Killer’s Apprentice” with Dr. Katherine Ramsland and has conducted research into John Wayne Gacy and sex trafficking networks.

She also served as an executive producer on The Serial Killer’s Apprentice documentary, helping bring new perspective to the story of Elmer Wayne Henley Jr. And Dean Corll.