The adventures of the popular time-traveling mouse Geronimo Stilton and his friends continue! This time, Geronimo's enemies the Pirate Cats have accidentally traveled back in time and wound up smack dap in the middle of the Ice Age! They decide to capture a great Wooly Mammoth and bring it back to the present to collect fame and fortune. Can Geronimo and friends stop the Pirate Cats' latest scheme in time?