Michael Louis Diamond, also known by his stage name Mike D, is an American musician, rapper, actor and writer. Born to a Jewish family in New York City, he is best known as a part of the hip-hop trio 'Beastie Boys' alongside his high school friends, Adam "Ad-Rock" Horovitz and Adam "MCA" Yauch, formed in 1981. The group disbanded after Yauch died due to cancer in 2012, shortly after they were inducted into the Rock and Roll Hall of Fame. As well as featuring in the group's music videos, Diamond has made cameos in other music videos and shows, as well as DJing. He has two children with director Tamra Davis, and co-wrote the 2020 documentary 'Beastie Boys Story'.