At last, the king of the Cretaceous makes his appearance. The Tyrannosaurus rex is perhaps the best-known of all dinosaurs, and partly because of that, I held back on the “t-rex”, saving him for the last book. But also, I saved him for a particular role, that of the scariest monster in the series. The Guardian of the Gates of the Dead is about as sinister and frightening as they come. He is the dinosaur equivalent of Cerberus, the three-headed hound that guarded the underworld of ancient Greece and Rome, but also a creature called Ammit from ancient Egypt. He is the devourer of souls, but as I explain in the novel, when he eats you, not only do you cease to exist, but you cease ever to have existed at all. All memory of you, all impact you might have had in your life, or in my story, in death, disappears with you down the gorge of this, the largest predator every to have walked the earth.