As Tilly, Oskar, Alessia and Milo venture into Arthurian legend to find the first bookwanderer -- the wizard Merlin -- they discover that everything they thought they knew about bookwandering might be wrong. Working together to figure out how to untangle the Alchemist's grip on the world's imagination, save Pages & Co., and defeat an unexpected enemy, they learn about the true power of imagination in a journey through myths and legend that will help them to save the very foundations of bookwandering...