Behind the Eight Ball (1942)

The story takes place at a summer theater in the Berkshire Mountains, where heroine Joan Barry (Carol Bruce) is staging a Broadway-bound musical comedy. Only one problem two guest stars are shot and killed on two successive evenings, right in front of the audience. Hoping to solve the mystery, detective William Demarest demands that everyone -- actors and theatergoers alike -- return the following weekend to restage the show. But with no major performer willing to assume the fatal guest-star slot, Joan is forced to hire the Three Jolly Jesters (Al, Harry and Jimmy Ritz), Manhattan washroom attendants with showbiz aspirations.