In the darkness behind a Hollywood apartment building, Sal Mineo screamed for help shortly before dying from a stab wound to the heart in February 1976.

It was a shocking end for the beloved actor, who had starred in classics like Rebel Without a Cause, Giant and Exodus. Yet in the aftermath of this tragedy, the question of who killed Sal created mountains of speculation — which nearly allowed a killer to walk free.

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Sal in 1970.

Sadly, 40 years after Sal’s death, those rumors are still often mistaken for the truth. “At first the police dismissed it as a homosexual murder,” explained Michael Michaud, author of Sal Mineo: A Biography, as he helped Closer separate fact from fiction in one of Hollywood’s most notorious crime cases.

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Sal made a name for himself playing brooding teenagers early in his career, and was living as a heterosexual. But by age 37, things had changed drastically: Sal was living with his male lover, Courtney Burr, rehearsing a high-profile play and scheduled to direct his first feature film for MGM. “There were good things going on in his career,” says Michaud.

To read the full story on Sal, pick up the new issue of Closer Weekly, on newsstands now!