Born October 31, 1967 in South Orange, New Jersey. He moved to Manhattan when he was very young, and that was where his father, now-renowned playwright Israel Horovitz, started his theater, the Gloucester Stage Company. Adam's parents divorced when he was 3 years old. His older siblings, Rachael and Matthew, lived with his father, while Adam stayed with his mother. His mother, Doris Keefe Horovitz, died of alcoholism when Adam was in his teens. He was in a New York thrash band called The Young and the Useless before joining the Beastie Boys in 1983. He plays a wide variety of instruments, including guitar and keyboard. Adam made his feature film debut in Lost Angels, a film directed by Hugh Hudson. He has starred earlier in 2 films with the other Beasties, Mike Diamond and Adam Yauch; 1985's Krush Groove and Run DMC's Tougher than Leather. He moved to California in 1989 with the other Beasties and married actress Ione Skye sometime between 1991-93. (Rumors have been circulating that they are now divorced and Ione is in a relationship with Bikini Kill's Kathleen Hanna but it's a good chance that stuff is bullshit.)