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1. Biggie Smalls: Like Chasen, Smalls was in a car (or SUV, in the rapper's case) around midnight, and on his way out of an all-star bash (a Soul Train Music Awards afterparty near L.A.'s so-called Miracle Mile) when multiple shots were fired into his vehicle. No arrests have ever been made in connection with the March 9, 1997, slaying, which occurred six months after Smalls' hip-hop rival, Tupac Shakur, was killed in similar fashion in Las Vegas.
2. Sal Mineo: The two-time Oscar-nominated actor (Rebel Without a Cause, Exodus) was returning from a play rehearsal when he was stabbed to death outside his West Hollywood apartment on Feb. 12, 1976. There was no suspect, but plenty of speculation, with press reports citing "the drug angle," and so-called "homosexual overtones." (Mineo was not out, per se—few were back in the day.) Three years after the killing, a jury found a 22-year-old man guilty of a nothing more senseless than murdering Mineo during a botched robbery.
3. Sharon Tate: The brutal Aug. 9, 1969, slayings of director Roman Polanski's movie-star wife (Valley of the Dolls) and four others at the couple's Benedict Canyon mansion puzzled police, and put Hollywood under a microscope. Had "narcotic aspects" been at play? Were Tate and her friends killed as part of a "drug-and-sex ritual?" Then, four months after the killings, the world met Charles Manson.
4. Elizabeth Short, aka The Black Dahlia: The aspiring actress has starred in Hollywood's most infamous murder mystery since the gruesome discovery of her halved body in the Leimert Park area of L.A. on Jan. 15, 1947. Through the years, the case has produced confessions, books and movies—but not one definitive answer.
5. Barbara Colby: The tough-talking character actress was familiar to fans of The Mary Tyler Moore Show, and was a series regular on the MTM spinoff Phyllis, when she and fellow actor, James Kiernan, were shot and killed on July 24, 1975, as they returned to their cars from an acting school in L.A.'s Venice neighborhood. Police originally linked the slayings to a deadly robbery spree that left one other woman dead. But one month later, investigators said they had "no hard leads," and Colby's Hollywood friends, including Cloris Leachman, posted a reward. The murders of Colby and Kiernan remain unsolved.