The second book in the sensational Magnus Chase series from Percy Jackson creator Rick Riordan. Thor's hammer is missing again. The thunder god has a disturbing habit of misplacing his weapon - the mightiest force in the Nine Worlds. But 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 the hammer's return is the gods' worst enemy, Loki - and the price he wants is very high.

Rick Riordan (he/him), dubbed 'storyteller of the gods' by Publishers Weekly, is the author of five #1 New York Times best-selling middle grade series with millions of copies sold throughout the world, including Percy Jackson and the Olympians, now a live-action series on Disney+. Rick is also the publisher of an imprint at Disney-Hyperion, Rick Riordan Presents, dedicated to finding other authors of highly entertaining fiction based on world cultures and mythologies. He lives in Boston, Massachusetts with his wife and two sons. Follow him on Twitter at @RickRiordan.