Someone is killing elderly women in Trenton and leaving them in dumpsters. Since the murders take place elsewhere and the dumpsters disguise any clues that could be useful, the police are at a dead end. One of the victims is the mother of Ranger's client, and he wants Ranger to investigate. So Ranger hires Stephanie Plum to help with the investigation. Then the fun begins.
When the series began, Stephanie was recently unemployed and in desperate need of a job. So she allowed herself to be talked into working for her cousin, Vinnie. Vinnie owns a bail bond