Making his feature film debut in william Wyler's 1956 film Friendly Persuasion, Richman was, by that time, already a regularly employed television actor, as well as a member of New York's Actors Studio, a resource of which he would avail himself frequently until moving to Los Angeles in 1961. He is perhaps best known for his role as Nicholas "Nick" Cain in the 1961 films The Murder Men and The Crimebusters. He reprised his role as Nicholas Cain in the NBC television series Cain's Hundred. Richman's other TV roles were on the soap opera Santa Barbara as Channing Creighton 'C.C.' Capwell (1984), Longstreet as Duke Paige, on the ABC soap opera Dynasty as Andrew Laird (1981–1984), and a recurring role on Three's Company (1978–1979) as Chrissy's father, Rev. Luther Snow. Guest star on Beverly Hills, 90210. His other films include Friday the 13th Part VIII: Jason Takes Manhattan (1989) and Vic (2005).