The True Story Behind Apple TV+’s The Crowded Room

After a shooting takes place outside New York City’s Rockefeller Center, the investigation that follows unearths secrets buried deep inside the mind of the young man accused of the violent crime, Danny Sullivan (Tom Holland), in Apple TV+’s new limited series The Crowded Room.

Set in 1979, the 10-episode psychological thriller is told through a series of interviews with a professor who is brought in to interrogate Danny, Rya Goodwin (Amanda Seyfried). The first three episodes of the show are set to premiere on June 9, with a new episode dropping every Friday through July 28.

Created by Akiva Goldsman, the Oscar-winning screenwriter of A Beautiful Mind, The Crowded Room is inspired by the true story documented in Daniel Keyes’ 1981 non-fiction novel The Minds of Billy Milligan. Keyes’ book chronicles the life and trial of Milligan, the first defendant to ever be found not guilty due to dissociative identity disorder (previously called multiple personality disorder).

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While the series borrows from Milligan’s case, it’s not a straight adaptation of real-life events. “For me, it was about really creating empathy—to create a character that you would really ally with,” Goldsman told Entertainment Weekly of Holland’s role. “That you would feel connected to and so his journey would become the audience’s journey.”

Here’s what to know about the real man who inspired The Crowded Room.

Who was Billy Milligan?

In 1977, 22-year-old William “Billy” Stanley Milligan was arrested for the kidnapping, robbery, and rape of three women around the Ohio State University campus area. While undergoing a psychiatric evaluation following his arrest, Milligan insisted that a man named Ragen was responsible for the robberies while a woman named Adalana had committed the rapes.

By the time his case went to trial, doctors had determined that Ragen and Adalana were two of 10 alternate personalities that existed within Milligan’s mind as a result of severe physical and sexual abuse he had allegedly suffered at the hands of his stepfather, Chalmer Milligan, as a child. He was later diagnosed with an additional 14 identities.

In December 1978, Milligan was acquitted of his crimes by reason of insanity caused by dissociative identity disorder. The court decision was the first of its kind and remains controversial to this day. Netflix previously released a docuseries exploring Milligan’s life, Monsters Inside: The 24 Faces of Billy Milligan, in 2021.

What happened to Billy Milligan?

After being found not guilty, Milligan was institutionalized in state-run psychiatric hospitals for several years. On July 4, 1986, he escaped from Central Ohio Psychiatric Hospital and relocated to Bellingham, Wash., under the alias Christopher Carr. He left Washington state a few months later after his roommate, whom he was suspected of murdering, disappeared. He was picked up by police in Florida soon after and returned to an Ohio psychiatric hospital.

Milligan was ultimately discharged from the hospital in 1988 after psychiatrists concluded that his many personalities had fused into one harmless one as a result of therapy and he was no longer a danger to society, He subsequently underwent outpatient mental treatment before being released from all state supervision in August 1991.

In 2014, he died of cancer at the age of 59 at a hospital in Columbus, Ohio.