65 million years ago, Grog the caveman fell asleep under the sun. He snored, enjoying a long nap. He dreamed he was chasing a dinosaur, and that the dinosaur was afraid of Grog's mighty club. It was the dinosaur that ran, and it was Grog who was triumphant.

But then Grog was woken up -- by the roaring of a real dinosaur. And his day was only going to get worse …