The Hammer of Thor (2016) by Rick Riordan is the second book in the Magnus Chase and the Gods of Asgard fantasy series, preceded by The Sword of Summer (2015) and followed by The Ship of the Dead (2017). The Hammer of Thor picks up a few weeks after the events of The Sword of Summer, and a cast of new and returning characters race against time to stop the trickster god Loki from being freed. The Hammer of Thor received the Stonewall Book Awards Children’s & Young Adult Literature Award (2017) for its merit in portraying the LGTBQ experience, and it has been translated into over 15 languages. Before transitioning to writing, Riordan taught mythology to middle schoolers, and a lifelong interest in Norse myth led him to pen the Magnus Chase series. This guide follows the 2016 Disney Hyperion version of The Hammer of Thor.

Note: The character Alex Fierro identifies as gender-fluid. The source text makes it clear that she prefers not to use the gender-neutral pronoun “they” and instead uses the pronoun that aligns with her identity at a given moment. As the source text states that she most often identifies as female, the guide uses she/her pronouns when referring to Alex generally and uses he/him pronouns in addressing specific scenes in the novel in which Alex identifies as male.

Plot Summary

The Hammer of Thor begins six weeks after the closing of The Sword of Summer. Protagonist Magnus Chase and his friend Samirah al-Abbas (“Sam”) are supposed to meet an informant for news of Thor’s missing hammer, but Sam has to leave to perform Valkyrie duties. Magnus meets with the informant, one of Thor’s goats named Otis, but the goat is killed by a masked assassin who warns Magnus not to listen to Otis’s information. Unsure what to do, Sam and Magnus return to Valhalla for the evening combat and welcoming of the newest einherji (soldiers in Odin’s army)—Alex Fierro, who is a child of Loki and is therefore Sam’s sibling.

Alex does not acclimate to Valhalla well, making Magnus and his friends wonder if Alex is a spy for Loki. During combat, Magnus learns that Alex is gender-fluid (meaning she identifies as male or female at different times) and that she has a deep understanding of Loki’s power. At dinner, Magnus and Sam decide to ignore Otis’s assassin and search the tomb where Thor’s hammer may be hidden. Earlier that day, Loki visited Sam’s family to announce Sam would be wed to a giant. Sam is determined not to go through with the wedding, but the announcement left her to explain her Norse activities to her betrothed, Amir, who struggles to understand.

The next day, Magnus and Sam, along with their friends Blitz and Hearth, go to the tomb, where they easily defeat the guardians, only for Loki and Magnus’s uncle, Randolph, to arrive. Loki and Randolph take the weapon in the tomb—which is the powerful Skofnung Sword and not Thor’s hammer—mortally wounding Blitz in the process. The wound can only be healed by the Skofnung Stone, partner to the blade, which Hearth’s father has. Magnus prays to his father, the god Frey, to open the tomb, and sunlight pours in, turning Blitz to stone and preserving him barely alive.

While Sam returns to Midgard, Magnus and Hearth take a petrified Blitz to Alfheim (realm of the elves) to ask Hearth’s father, Mr. Alderman, for the Skofnung Stone. Mr. Alderman blames Hearth for the death of Hearth’s brother many years ago and will only hand over the stone when he feels Hearth has atoned for his actions. With the help of a nature spirit in the employ of Mr. Alderman, Magnus and Hearth fulfill the terms and restore Blitz to life, healing his wound. As a result of Magnus and Hearth paying Hearth’s debt, Mr. Alderman’s personality seems to change, and he becomes frenzied and hostile. Magnus, Blitz, and Hearth escape—Blitz and Hearth to the dwarven realm and Magnus to Midgard, where he meets up with Sam, Amir, and Alex.

Using his Frey abilities, Magnus helps Amir see the Norse world for what it is, and the group traverses the rainbow bridge to Asgard, where they ask the bridge guardian for help finding Thor’s hammer. The guardian doesn’t find the hammer, but he does see a message from a giant named Utgard-Loki for Magnus to come to Jotunheim (realm of the giants) for information. The next day, Magnus, Sam, and the others journey to Utgard-Loki’s bowling alley in Jotunheim, where they must prove themselves in exchange for Utgard-Loki’s information. They manage to defeat the giants in competitions, despite the giants trying to cheat, and Utgard-Loki reveals that the entire wedding is a ploy for Loki to get the tools necessary to free himself—namely the Skofnung Sword and Stone.

The giants chase Magnus and his friends out of Jotunheim and into Asgard, where Magnus and company make a plan with Thor to stop the wedding. The day of the wedding, Alex and Sam switch places as an extra precaution, and the group is taken to the chamber where Loki has been bound for centuries. Though they fight well, Magnus’s uncle Randolph manages to free Loki, and the two escape before Magnus’s godly backup arrives. Thor retrieves his hammer, and the group returns to Valhalla, where they learn Loki will spend the next few months preparing to sail the Ship of Nails to begin Ragnarok (the end of the world). Needing help dealing with the gods, Magnus meets with his cousin Annabeth, a daughter of the Greek goddess Athena, and Annabeth says she’ll bring her boyfriend, Percy, along to aid in the coming battle.