Early in the film, Mrs. Howard tells Bob that his publisher, Mr. Wright, called from New York. Weird Tales, edited by Farnsworth Wright, was actually published in Chicago.
The door of the car that won't start shuts itself.
When the school principal welcomes the teachers for the new school year, the U.S. flag in the background has 50 stars, whereas in the 1930s the flag would have only had 48 stars.
The postcard Novalyne gets from Bob shows a green 1¢ stamp featuring Andrew Jackson that was issued in 1963, yet the film is set in the 1930s.
Enid says that Bob Howard thinks he's "Max Schneling" when he is pretending to box. The German boxing champ's name was actually Max Schmeling.