R. J. Spencer is a lucky 12-year-old. He lives in the big city and his parents are landlords of the high-rise apartment building that is his home.
The many tenants in the building, along with the endless possibilities of adventures in the city itself, are the perfect setting for the young detective as he sets out to solve every case he can get his hands on.
R. J. and Joey are very excited about the summer, especially their favorite daily treat of ice cream. Then the worst thing possible occurs and one day Mr. Pip's ice cream truck is nowhere to be seen. Will R. J. and Joey be able to track down the strange guy who seems to be responsible for the disappearance of Mr. Pip and their daily treat?