Peregrine, an impoverished seventeen-year-old student, from an alternative version of Earth, embarks from Menschens Portal Emporium, on a quest to find the key to a mysterious portal and lock out an army of the most fearsome creatures in literature. In a multi-reality universe, there is no distinction between fact and fiction, and characters first created in novels live independent lives. In an alternative London of 1880, three former characters from the David Copperfield novel ask Peregrine for asylum in his home world of Earth Minor, a planet-size satellite. On his return, Peregrine finds that a rival has blackmailed his girlfriend, Montana, into signing a legal marriage contract. The convicted clerk, Uriah Heap, unexpectedly comes to the rescue with a terrifying ultimatum. As the climax intensifies, Peregrine enters a nightmare reality where his whole life is a play, and an actress takes the part of his beloved Montana. She is the exact double of Montana but says that her name is Julia, and she has a life that does not include Peregrine. Who is the real Montana? Does the reality where they met and fell in love still exist, and can he ever return?