Jamie and Tom are off for another adventure in Dino World, through their secret smuggler's cave.

This time they decide to try crabbing - and they manage to catch a real prehistoric crab!

Jamie looks it up in the Fossil Finder, and then the boys settle down to have a really good look at their Dino Crab.

But then disaster strikes! A sneaky Velociraptor runs up and grabs the Fossil Finder!

The boys have to get it back - if they don't, then in the future scientists might find their computer buried with a dinosaur fossil - and that could mess up the whole of dinosaur science!

So the chase is on. But the Velociraptor is fast and cunning and leads the boys into a valley full of geysers spouting hot water!

Can they find their way through and get their Fossil Finder back - or is the sneaky Velociraptor just too speedy?