"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...

"Imagine a vault so cavernous that it could contain all the world's greatest treasures and relics, from mummified remains of ancient monarchs to glistening swords brandished by legendary warriors. How could someone come into possession of such a collection? Who is Professor Brownstone? Hear the story of the very first items in this collection as we journey to the land of the Vikings--a place filled with magical objects, powerful gods and mythical...