[5] Mystery author Cornelia Van Gorder rents The Oaks, a summer home in a small town, from local bank president John Fleming.

While on a hunting trip with his physician, Dr. Malcolm Wells, Fleming confesses to stealing over $1 million in negotiable securities from the bank.

He offers to split the money with Wells in return for help faking his own death and threatens to kill him if he does not comply.

As they lock up The Oaks that night, Lizzie sees the Bat's clawed hand reaching through an unlocked window.

When Wells leaves to answer Van Gorder's call, Anderson breaks into the laboratory and searches it.

Anderson tells the women to lock themselves into their rooms for the rest of the night; he will stay to watch for the Bat.

She accidentally traps herself in the room, but is freed by Detective Davenport, the officer assigned to watch the house that evening.

The Bat returns to Van Gorder's house, where he sets the garage on fire to draw the occupants outside.

Warner unmasks the Bat, who is revealed to be Lieutenant Anderson, whose motives were financial, as he was one of the first people notified of the theft of the bank securities later converted into cash.

Cast notes RKO Pictures bought the rights to remake The Bat from Mary Pickford, who produced the original 1926 film adaptation for United Artists,[6] the studio she founded in 1919 with Douglas Fairbanks, Charles Chaplin and D. W. Griffith.

[7] According to Turner Classic Movies, in an era of films featuring "rampaging aliens and sinister ghouls", The Bat's period piece approach was not a crowd pleaser, although its reputation has improved over time.

[9] In a contemporary review of the film, The New York Times praised Moorehead's "good, snappy performance" and Crane Wilbur's direction.