In the early 1970s, Flynn was one of the leaders of a Screen Actors Guild group that sought a more equitable distribution of TV residual payments. On July 19, 1974, just after completing his voice-over work on the Disney animated movie The Rescuers (1977)," he died of a heart attack in the swimming pool of his Beverly Hills home. Apparently, he had gone into the pool with a cast on his broken leg. His body was found at the pool's bottom, held down by the weight of the cast. He was 49 years old.