One night, Spike creeps downstairs in his pyjamas to find that his granny has turned into a dinosaur -- Grannysaurus! There are dinosaurs boogying in the living room. With Brontosaurus, Stegosaurus and Giganotosaurus, it's a dino disco! Spike wants to stay up and party too! How will Grannysaurus ever get him back to bed? Perhaps her next guest, Tyrannosaurus Rex, can help?