When an eccentric professor acquires an ancient book, a riddle on a spare piece of parchment tucked neatly within its pages leads him and his nephew on an unparalleled adventure. The unlocked riddle brings them to a remote mountain on Iceland, where they enter an extinct volcano on a daring quest to reach the center of the earth. They soon find themselves at a giant underground ocean where the laws of science are constantly redefined and prehistoric creatures are in abundance. But in the bowels of the Earth, a shocking discovery pits the travellers face to face with their own terrifying past.