In Billy Wilder's noir classic, "Double Indemnity", when insurance salesman Walter Neff first meets femme fatale Phyllis Dietrichson, she asks "Neff is the name, isn't it?" Neff wisecracks back, "With two f's...you know the story...the Philadelphia Story!" An in-joke about Philip Barry's smash stage comedy. Only it hit Broadway in 1939, the year after "Indemnity" occurs, 1938.

Equally anachronistic is the music overheard throught the window when Walter and Phyllis meet for the last time. It's "Tangerine" by Victor Scherzinger, and it wasn't composed until 1942!