Nine years after they came together to defeat the Winter King, John, Jack, and Charles return to the Archipelago of Dreams and face a new challenge involving the Lost Boys and giants.
The Winter King's Shadow, having gained control of the doors from the Keep of Time and of an army of Dragon Shadows, plans to use the turmoil of World War II to conquer worlds, but all Caretakers, past and present, come together to stop him, using some unlikely weapons.