The fictional film which George Gobel and Diana Dors are watching in the cinema is a Technicolor film "Forever and Forever and Forever" starring John Wayne and Angie Dickinson.
Although with film was completed in the latter half of 1956 at RKO, it wasn't released until 1958 as part of a deal with Universal-International which took over distribution of completed RKO pictures as that studio had closed down operations by the end of January 1957.
Second and last feature film to star George Gobel, the first being his debut in The Birds and the Bees (1956). He would not appear in another film until The Day It Came to Earth (1977).
Mickey says that the actress in the John Wayne movie was probably married to someone else in real life. Angie Dickinson was indeed married--to Gene Dickinson--when the film was shot.
Filmed between mid-July and late August 1956, the movie's run in Los Angeles began on May 14, 1958.