This article mentions sexual assault.

Summary

• Split draws inspiration from Billy Milligan, the first person to use multiple personality disorder as a defense and succeed.
• In the 2016 film, Kevin Wendell Crumb has dissociative identity disorder with 24 separate personalities.
• Kevin's story mirrors Milligan's in multiple ways, as the latter also had 24 personalities, some of whom committed similar crimes to those shown in the film.

M. Night Shyamalan's Eastrail 177 trilogy, which began with Unbreakable in 2000 and ended with Glass in 2019, drew from real-life inspiration for its middle installment, Split. Split explores dissociative identity disorder through its main character, Kevin Wendell Crumb, who is played by James McAvoy. At the beginning of Split, Kevin kidnaps three girls and holds them hostage in an undisclosed location. At first, they interact with an austere, serious man who goes by the name of Dennis and is obsessed with cleanliness. Later, they meet other personalities, such as Patricia and Hedwig, with their own distinct mannerisms.

All of this culminates at the ending of Split, with Kevin's 24th personality, The Beast, emerging and granting him almost supernatural strength and speed. Split is very much a metaphor for how someone who has endured trauma can develop strategies to cope, and in the end, Kevin addresses that his childhood abuse and trauma has literally made him stronger. Though it certainly seems like a fictional tale, and dissociative identity disorder (DID) is widely misunderstood and stigmatized, Shyamalan drew from a true story for inspiration.

Split's Kevin Was Based On The True Story Of Billy Milligan

He Was The 1st Person To Use Multiple Personality Disorder As A Court Defense & Succeed

Kevin's character in Split is based on a real person named Billy Milligan, who was the first person to use the defense of multiple personality disorder (now referred to as dissociative identity disorder) in a court case in the United States and be found not guilty (via Esquire). Milligan was first arrested and imprisoned in 1975 for rape and armed robbery. However, he was released in 1977 and required to register as a sex offender. Milligan ended up in jail again in 1977, not long after his initial release, for kidnapping, robbing, and raping three women near Ohio State University.

It later came out that Milligan was abused by his step-father, Chalmer Milligan, which psychiatrists confirmed caused multiple personalities to develop.

Milligan was caught because police found his fingerprints, and he was identified using his former mug shots. Milligan's victims reported odd behavior from him, with one revealing that he spoke to her in an accent and another suggesting he was charming at times (via The Columbus Dispatch). It later came out that Milligan was abused by his step-father, Chalmer Milligan, which psychiatrists confirmed caused multiple personalities to develop. The one who attempted to rob the women near Ohio State University was a young Yugoslavian man named Ragen, while 19-year-old Adalana reportedly raped them.

What Happened To Billy Milligan

The Man Who Inspired Split Laid The Groundwork For Other Projects As Well

After Milligan's arrest, his trial drew a lot of attention because of his defense's use of his diagnosis to enter an insanity plea. Milligan's psychologists determined that he had 10 different personalities, at least at first. He was deemed not guilty and sent to Athens Mental Health Center rather than prison. Milligan was later transferred to other psychiatric hospitals, and he was found to have an additional 14 personalities by Dr. David Caul. He spent more than a decade in various psychiatric facilities until he was released in 1988 — though he escaped at one point in 1986 and was arrested once again.

Although Milligan never possessed any of the physiological strengths and superhuman abilities that Kevin does in Split, it's also easy to see how his experiences might have inspired Shyamalan's 2016 movie.

The controversy surrounding Milligan died down after his release, though his story laid the groundwork for further studies centered on dissociative identity disorder. It was also covered in Daniel Keyes' 1981 book, The Minds of Billy Milligan, and a Netflix documentary called Monsters Inside: The 24 Faces of Billy Milligan. Although Milligan never possessed any of the physiological strengths and superhuman abilities that Kevin does in Split, it's also easy to see how his experiences might have inspired Shyamalan's 2016 movie. Milligan died in 2014, when he was 59 years old.

Source: Esquire, The Columbus Dispatch