Garr appeared in a string of highly successful films in the mid-to-late 1970s, including a supporting role in Francis Ford Coppola's thriller "The Conversation" (1974). This was followed with her role as Inga, an assistant to Dr. Frederick Frankenstein, in the Mel Brooks horror comedy "Young Frankenstein" (1974), which marked a career breakthrough. She then appeared in a dramatic role in Steven Spielberg's science fiction film "Close Encounters of the Third Kind" (1977) as the wife of Richard Dreyfuss's character; in "Oh, God!" (1977) as the wife of John Denver's character; and the drama "The Black Stallion" (1979) as the mother of the boy protagonist.