Claim: Tommy Chong was in That '70s Show.
Evidence: Thomas B. Kin Chong -LRB- born May 24 , 1938 -RRB- is a Canadian-American comedian and actor , who is 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.