Fair-haired and often mustached character actor Seymour Cassel began making film and TV appearances as scruffy hippie types in the 1960s. He studied at the American Theatre Wing and the Actor's Studio before making his film debut in John Cassavetes' first film, Shadows (1959), for which he also served as associate producer. He then co-starred with Cassavetes in Too Late Blues (1961) and The Killers (1964). When Cassavetes turned to directing full-time, he utilized Cassel's talents as often as possible. The actor was Oscar-nominated for his portrayal of an aging hippie in Faces (1968) and later played Moskowitz in Minnie and Moskowitz (1971).
A somewhat heavier Seymour Cassel continued as a character actor over the next few decades with roles in Tin Men, Colors, and the made-for-TV movie Blood Feud. In the '90s, he played Sam Catchem in Warren Beatty's Dick Tracy, dog-sled adventurer Skunker in the Disney classic White Fang, and a chauffeur in Indecent Proposal. His role as the shyster Joe in the black comedy In the Soup also earned special recognition at Sundance. Cassel then appeared in two romantic comedies with director Andrew Bergman: It Could Happen to You and Honeymoon in Vegas. For the rest of the '90s, his career prospered with small, but memorable, roles in such independent comedies and dramas as Things to Do in Denver When You're Dead, Trees Lounge, and Dream for an Insomniac.
During this period, he developed a rapport with filmmaker Wes Anderson, who would cast him in many of his projects. Cassel would play Max Fisher's barber father in Rushmore, Royal's friend Dusty in The Royal Tenenbaums, and Steve's late friend Esteban in The Life Aquatic, Cassel would also continue to work consistently in all areas of film, appearing notably in comedies like Stealing Harvard, Stuck on You, Beer League, and L!fe Happens.