When Barnaby and Jedediah go out of town a relative of Betty's calls her to ask for help. It seems he suspects that his father who supposedly died in an accident, was actually murdered. Betty agrees to meet him but when she arrives she finds him dead of an apparent suicide. But the police tell her, it appears that he was murdered. In the meantime, the Tarkington Detective Agency is called by the insurance company who had a policy on her cousin to investigate. Now the head of the Agency William Tarkington IV, who is a pompous twit thinks Betty killed him when clearly she didn't. But he pursues that avenue and Betty also tries to find out what happened and she discovers other relatives who died mysteriously. When Tarkington learns of this he investigates and discovers that Betty has an aging aunt who is rich and that someone is trying to make sure that they alone get the aunt's money. And he changes his mind about Betty when someone tries to kill her.
