Bruce Richmond is gambler who is worried about his cat-loving aunt Adelaide Snow telling everyone he is a check forger. He cooks up a scheme where where he will lock his aunt in the bank vault in her house before he goes on vacation. He hopse she will suffocate and that her death will be ruled an accident. He locks Adelaide in the vault with one of her cats. While on vacation, Bruce's wife Lorna gets worried when she calls Adelaide and recieves no answer. She demands that they return from their vacation. Lorna and Bruce arrive at Adelaide's home and finds nothing. Lorna assumes that Adelaide's must have left the house for the weekend. Bruce almost gets away with murder, until Lorna hears Adelaide's cat wailing inside the vault. Lorna opens the vault and Bruce realizes that he's been caught.