Netflix has released the trailer for Monsters Inside: The 24 Faces of Billy Milligan, a four-part documentary series that tells the story of the first person to be acquitted of a major crime due to Dissociative Identity Disorder (referred to as Multiple Personality Disorder in the 1970s).

Milligan’s case baffled police detectives and psychiatrists alike, because the more he talked, the more complicated it became to determine if he really had a psychiatric disorder or was just faking extremely well in order to escape conviction. The docuseries will premiere on September 22nd.

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Image via Netflix

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All episodes were directed by Olivier Megaton (The Last Days of American Crime), and his investigative take led him to interviews with the Milligan family, Milligan's former friends, doctors, and the law enforcement professionals who tried to untangle the truth. It’s been more than 40 years since the verdict and there are still no definitive answers about the Milligan puzzle.

This is not the only story about Billy Milligan about to hit our screens. Back in April, Apple announced The Crowded Room, an anthology series about mental illness. The first 10-episode season, starring Tom Holland, will be based on the Billy Milligan biography by author Daniel Keyes.

Monsters Inside: The 24 Faces of Billy Milligan comes to Netflix on September 22. Check out the trailer and synopsis for the series below.

In 1977, a serial rapist struck Ohio State University. Overwhelming evidence quickly led investigators to Billy Milligan, an aimless young man with a traumatic childhood and a criminal record. Yet upon his arrest, Billy had no memory of the assaults, and his mannerisms seemed to change on the spot. A parade of psychiatrists diagnosed him with multiple personality disorder (now known as dissociative identity disorder), eventually determining that as many as 24 distinct “multiples” existed within his mind. In a case that captivated the nation, their analysis anchored a first-of-its-kind legal defense strategy, and Billy was found innocent by reason of insanity. His trials, however, were far from over.

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