GERONIMO STILTON Book 14: THE TEMPLE OF THE RUBY OF FIRE
Geronimo's old friend, Professor Paws von Volt, sends the gang airplane tickets so they can join him on the Amazon River. While they wait to meet up with the professor, a tail-pinching crab, a prickly sea urchin, stinging jellyfish, and an injection-happy doctor all target Geronimo. Is he having fun? NO.
At last, the professor arrives --- in the coolest submarine ever. He asks for their help in finding an ancient Incan temple, which holds an enormous ruby. Evil rodents that are destroying the rain forest complicate the group's quest. As the adventure unfolds, Geronimo learns some fascinating history. He also discovers how to improve the future of our world.