Best friends Samuel and Anna are on a museum excursion to see real dinosaur fossils. For the two dino lovers, this seems exciting enough. Then, a magical collision in time awakens Norus, guardian of the exhibits. He needs Samuel and Anna to go back in time to retrieve an ammonite and an allosaurus tooth. Are they up for the challenge, even if it means putting their own lives at risk? A heart-thumping adventure filled with bite-sized facts about dinosaurs, fossils and prehistoric life, and illustrations that bring the story to life.