When Jamie moves to Dinosaur Cove with his father he's looking forward to doing some fossil hunting on the beach. But when he and his friend, Tom, discover a forgotten cave with fossilised dinosaur footprints, it takes them to another world ...a world of dinosaurs.

In this secret place the boys meet a small, friendly Wannanosaurus, who leads them further into the prehistoric landscape, past mysterious fungi and strange fruits (which smell like sick!).

But when the ground starts to shudder and the Wannanosaurus runs off at lightning speed, the boys know they're in serious danger. The Tyrannosaurus Rex has spotted them and he's coming their way ...Can the boys outwit the T-Rex? Will they be able to find their way back to the cave? And can they make it to their own world before the tide comes in?