Marx Brothers appeared, sometimes with Chico and Zeppo caricatured, in cartoons starring Mickey Mouse, Flip the Frog and others. In the "Airwolf" episode 'Condemned', four anti-virus formulae for a deadly plague were named after the four Marx Brothers. In "All in the Family", Rob Reiner often did imitations of Groucho, and Sally Struthers dressed as Harpo in one episode in which she (as Gloria Stivic) and Rob (as Mike Stivic) were going to a Marx Brothers film festival, with Reiner dressing as Groucho. Gabe Kaplan did many Groucho imitations on his sit-com "Welcome Back, Kotter" and Robert Hegyes sometimes imitated both Chico
Marx Brothers Cream" sketch. In a 1969 interview with Dick Cavett, Groucho said that the two movies made with Thalberg were the best that they ever produced. Despite the Thalberg films' success, the brothers left MGM in 1937; Thalberg had died suddenly on September 14, 1936, two weeks after filming began on "A Day at the Races", leaving the Marxes without an advocate at the studio. After a short experience at RKO ("Room Service", 1938), the Marx Brothers returned to MGM and made three more films: "At the Circus" (1939), "Go West" (1940) and "The Big Store" (1941). Prior to the release