Thomas B. Kin "Tommy" Chong (born May 24, 1938) is a Canadian-American comedian, actor, writer, director, activist, and musician. He is well known for his marijuana-themed Cheech & Chong comedy albums and movies with Cheech Marin, as well as playing the character Leo on Fox's That '70s Show. He became a naturalized United States citizen in the late 1980s.