Oxygen True Crime unveils sixteen hours of never-before-heard confession tapes that could rewrite one of America’s most notorious cold cases. The Boston Strangler documentary promises explosive revelations about Albert DeSalvo’s controversial confession. Here’s everything you need to know before tuning in.
The Boston Strangler Quick Documentary Details
| Detail | Information |
|---|---|
| Premiere Date | Sunday, October 26, 2025 |
| Air Time | 6:00 PM ET/PT |
| Network | Oxygen True Crime |
| Runtime | 2 Hours |
| Production | This is Just a Test |
The Case That Haunted Boston
From 1962 to 1964, at least 11 women were brutally murdered in and around Boston, creating widespread panic across the city. The killings involved sexual assault and strangulation, leaving residents terrified to unlock their doors. Albert DeSalvo confessed to the crimes but was never formally convicted of the Boston Strangler murders, maintaining one of true crime’s most perplexing mysteries.

What Makes This Documentary Different
The documentary features explosive new evidence from long-lost confession tapes that were believed to be lost and never made public—until now. These recordings capture DeSalvo describing details about the murders, but the tapes reveal troubling inconsistencies.
As the recordings play, DeSalvo gets key details wrong and at times seems coached to give specific answers, casting doubt on his confession. This raises a chilling question: Did Boston convict the wrong man, or was there never just one strangler?
Key Voices in the Investigation
Casey Sherman, nephew of the final victim Mary Sullivan, plays a central role after securing the confession recordings. His decades-long quest for truth drives the documentary’s narrative. “My mother always questioned Albert DeSalvo’s confession and now I know why the Boston Police Department didn’t release any more of these tapes,” Sherman reveals.
The documentary also features commentary from sons of former Boston Police detectives who worked the original investigation, providing insider perspectives on how the case unfolded behind closed doors.
If you’re fascinated by unsolved mysteries and true crime investigations, explore our collection of gripping crime documentaries on streaming platforms.
The Confession That Never Held Up
DeSalvo was killed behind bars while serving out a sentence for another crime, just one day before he allegedly planned to recant his confession. His murder in 1973 ensured the truth died with him—or so everyone thought.
The newly uncovered tapes suggest DeSalvo may have confessed for reasons beyond guilt. Theories explored in the documentary include book deals, financial support for his family, and potential coaching by other inmates at Bridgewater State Hospital.

Modern DNA Evidence and Lingering Doubts
While 2013 DNA testing linked DeSalvo to Mary Sullivan’s murder, questions persist about whether he committed all eleven killings. The documentary doesn’t promise definitive answers but presents evidence allowing viewers to draw their own conclusions about this controversial case.
For more compelling true crime content, check out our guide to must-watch documentaries that shocked audiences.
How to Watch
The Boston Strangler: Unheard Confession premieres exclusively on Oxygen True Crime with multiple airings scheduled throughout the week. Cable and satellite subscribers can watch on the Oxygen channel, while cord-cutters can access content through streaming services carrying Oxygen programming.





