"Thor's hammer is missing again. The thunder god has a disturbing habit of misplacing his weapon-- the mightiest force in the Nine Worlds. This time the hammer isn't just lost, it has fallen into enemy hands. If Magnus Chase and his friends can't retrieve the hammer quickly, the mortal worlds will be defenseless against an onslaught of giants. Ragnarok will begin. The Nine Worlds will burn. Unfortunately, the only person who can broker a deal for...

When mythological gods posing as tourists begin arriving in Buzz's hometown of Crowmarsh, he and his best friend team up on a dangerous search for a mysterious myth-keeper while endeavoring to unlock their own burgeoning powers.