Joshlyn Weaver has always lived with a big secret. Ordinary kids spend their free time going to the movies, hanging out with friends, and searching on the internet. But for her, an evening at home usually means entering people's dreams. For many generations, her family has been part of a very powerful and very secretive society of dream walkers. Tasked with the responsibility of lowering the world's general anxiety—which only leads to war and strife in the waking world—their job has always been to stop nightmares before they go too far. By stopping nightmares while sleeping, they help to stop nightmares in real life. But when an ancient feud within the dream walker society resurfaces right when a seemingly unconnected series of very strange and very scary events start occurring during her dream walks, Josh finds herself in a race against time. The one true dream walker has never been known. Could she be the one?

Feodor is dead. But he isn’t gone. Every night, Josh’s dreams are full of his memories—his life, his inventions, and his descent into madness. With her best friend still in a coma, her boyfriend traumatized by his near-death experience, and her abilities as the True Dream Walker nowhere to be found, the temptation to use Feodor’s ideas to her own advantage is almost irresistible. As her grandfather schemes to take control of the dream-walker government, Josh and Will join forces with a deposed princess against him. But they’ll need help from both their friends and their enemies to stop Peregrine this time, and ultimately Josh will have to choose between saving the world and saving her relationship with Will.

Save Haley. Find Peregrine. Kill Feodor. Joshlyn Weaver has a list, and she’s going to check off every item or die trying. She needs to save Haley from the Death universe, hunt down her scheming grandfather, and force Feodor to return the souls he stole. Will would help her—if she’d let him. But since healing the broken bonds between them isn’t on her list, he’ll have to prepare to meet Peregrine on his own, and his investigation leads him to the dream-walker community’s strangest corners. When the Veil separating the Dream from the World begins breaking down, Josh and Will have to come together to stop Peregrine from destroying the balance between the three universes—and they’ll need Feodor’s help, which always comes with a price. With the three universes collapsing into one another, Josh must decide who she is and who she can trust in time to save the World, herself, and everyone she loves.