Tree Callister is not much of a private detective. His first client just turned up at the door, and he's 12 years old. What's more, the kid has the grand total of $7 with which to hire Tree to find his mother. Everyone on Sanibel Island, Florida, where Tree lives, thinks the former newspaper reporter is out of his mind. His only defender is his wife Freddie, and even she has doubts.Then a headless body shows up, along with a threatening thug, a couple of suspicious detectives, and a former girlfriend, now an ex-FBI agent, who suspects Tree knows more than he is admitting. Before long, Tree is up to his neck in the kind of murder and mystery he only imagined as a boy reading the private detective novels he loved.