A happy housewife named Marsha, hopelessly addicted to reading murder mysteries, overhears her loving husband discussing her upcoming birthday surprise. To her ears, though, it sounds like they are planning to murder her. With the assistance of her next-door neighbor, she tries to turn the tables on them.

When her own mother shows up for her birthday a day early, Marsha thinks she is in on the diabolical scheme. When her maid’s date, a policeman, shows up to take the maid out, Marsha thinks he is on to her poisoning attempt. Well, finally, just when you would think all this would be cleared up, Marsha’s intended victims discover what she has supposed, and decide to teach her a lesson by actually pretending to be murderers.