Now that all seven keys have been retrieved, the Brakebills crew gears up for the final leg of their quest. But as everyone starts to put their heads together, Julia is pulled away by a fellow god – Iris – who claims it is now Julia's time to move on. Reluctantly leaving the team behind, Julia embarks on what will become a rather short-lived journey into god-dom. After getting the fundamentals of what it means to be a "creator," Julia seems somewhat uncomfortable with the expectations of being a higher power. That discomfort only grows as her friends' calls for help grow in intensity, forcing Julia to return to them to help save the day.
Back in Fillory, the Fairy Queen comes face to face with Irene and in a move both expected and unexpected, hands over her own life and magic in an effort to save her people. While gallant, the sacrifice triggers a domino effect that turns the entire world of magic – and the lives of the Brakebills crew – upside down. The Fairy Queen's decision reveals an intricate web of deception and lies, that includes Fogg and is led by The Library, to seize total control of magic once it is brought back.
And brought back it is by the Brakebills crew who, after a little finagling by Quentin, devise a plan and make it to the Castle at the end of the world. Once inside, they meet the guardian and the creature kept hidden, the latter of which initially seems harmless. But when Eliot shoots it with the god-killing bullet, he unknowingly releases a body jumping creature more powerful than they imagine. Before that though, Alice uses the power of fairy dust to destroy the original seven keys, forcing Julia to emerge and create seven more from her own godly powers.
But as soon as the group gets the magic turned back on, Irene, Fogg and the other Library henchmen pop in, sealing the magic into the same contraption Alice was supposed to use. As punishment, the Brakebills crew has their memory wiped and is released back into the world of regular humans where the creature they thought they had killed emerges to "play."