It's Christmas Eve in Dinosaur Cove and Tom and Jamie are hoping for snow. There's just time to go and visit their dinosaur friend, Wanna, in their secret world of real dinosaurs, and wish him a merry Christmas. But when they emerge from the cave, the Jurassic jungle has disappeared and there's snow everywhere! And what's that in the distance? It's a herd of woolly mammoths - the boys are in the Ice Age! Jamie, Tom and Wanna set off on a snowy adventure with blizzards, avalanches, a sabre-tooth cat, and a young woolly mammoth that needs their help to get back to its herd. As they search for the lost herd the boys come across another unexpected discovery - something so amazing they can hardly believe it. This double-length story is something that readers can really get their teeth into and is non-stop adventure from the first page to the last.