Harry thinks he's too old for his bucketful of dinosaurs, but he's wrong. He can still call on their help, only he's not the only one who's grown up . . .

Harry has a pocketful of dinosaurs now. On his key-ring is a complete set of plastic B.U.Ds - Back-Up Dinosaurs. If he really needs help he can run his finger along a B.U.D. head-to-tail and it will arrive - life-sized! When Harry hears that Mr Oakley has been robbed by a nasty crook, he thinks he and his friends - Jack, Charlie and Siri - can solve the crime. And after a night-time visit from Spinosaurus, he knows there are lots of friends he can call on for back-up.