Anachronisms: Although the movie is set in 1948, several cars from as late as the mid-1950s can be seen in the background in certain scenes.
Continuity: At the end, Jenny says she wants to go back and get her pillow; they never make it to her house. Nonetheless, in the final shot in the amusement park, there's the pillow.
Continuity: In Smitty's bar, Jenny's hamburger stays the same size, and even gets bigger, no matter how many bites she takes from it.
Continuity: When Dave Hirsch meets Professor French at Frank Hirsch's home they shake hands and drop their arms. In the next shot they are shaking hands again.
Revealing mistakes: Frank Sinatra's Army uniform lacks rank insignia. It is also without brass collar disks (U.S. emblem on one side and an infantry branch emblem on the other). Sinatra's character obviously served in the infantry, since he wears the Combat Infantryman's Badge above his left shirt pocket.