Bernie Rhodenbarr is a burglar and a sleuth. He is almost thirty-five years old, but opening locks and stealing things is the only trade he knows.
While drinking in one of his favorite bars, Bernie meets a stranger who offers him $5,000 to steal a box from the home of J. Francis Flaxford. The stranger seems to know about Bernie's many accomplishments as a burglar. Bernie has his reservations but he accepts a $1,000 advance and enters Flaxford's apartment when it is supposed to be empty. Almost immediately he is surprised by two cops. When one of them searches the apartment, he finds Flaxford murdered in the back bedroom. Bernie races from the apartment, convinced he has been set up by the stranger in the bar.
Bernie is now a fugitive from justice and he decides to hide out in the apartment of an actor friend who is away on a road trip. After a restless night, he is awakened by a girl who stops by to water the plants. The girl introduces herself as Ruth and takes an interest in Bernie's plight after she recognizes him from TV newscasts. Together they start to plan how Bernie can find the real killer.
They decide to begin by locating the stranger who set Bernie up in the first place. The stranger turns out to be an actor named Wesley Brill who was hired by Darla Sandoval to approach Bernie about the burglary. Darla wants to recover some incriminating photos from Flaxford who was blackmailing her. From this point on the plot takes a few neat twists aided by some incredible coincidences.
The book has a light-hearted tone, mainly because Bernie doesn't take life too seriously. Amidst a cast of clownish characters, two crooked policemen manage to stand out.