A long-gestating flick about the first person to successfully use the insanity defense at a U.S. trial is finally getting off the ground, with a major star attached.

The Hollywood Reporter writes that Leonardo DiCaprio is set to star in "The Crowded Room," the story of Billy Milligan, who was charged with robbery and rape in the 1970s. Milligan was subsequently diagnosed with multiple personality disorder, and pleaded not guilty by reason of insanity, claiming that two of his 24 personalities committed the crimes without his knowledge.

Per THR, "Milligan's various personalities included Adalana, a lesbian taking responsibility for the rapes; Ragen, a Yugoslavian communist who admitted to the robbery; and Arthur, an uptight Englishman." He was the first person to use -- and be acquitted for -- this defense.

Milligan's story was told in a 1981 book by Daniel Keyes, on which the film will be based; screenwriters Jason Smilovic ("Lucky Number Slevin") and Todd Katzberg ("Arms and the Dudes") will co-script the screenplay. DiCaprio had reportedly been interested in bringing the story to the big screen from as far back as 1997, and his "Titantic" director James Cameron was also reportedly circling the project at one time, but nothing ever came of the adaptation.

Now, according to THR, the film has new life, thanks to a partnership with New Regency, with whom DiCaprio is currently working on Oscar-winning director Alejandro Gonzalez Inarritu's "Birdman" follow-up, "The Revenant." New Regency will co-produce "The Crowded Room" alongside DiCaprio's own company, Appian Way.

[via: The Hollywood Reporter]

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