Forever, Darling (1956)

Susan and Lorenzo have been married for over five years and they are starting to drift apart. So into her life comes an angel, which only Susan can see, to tell her that there will be trouble ahead if they do not work out their problems. Lorenzo is developing insecticide #383 at Finlay Vega Chemical Co. and plans to test it on a camping trip that he takes with Susan, but the trip becomes an obstacle course for him.