In the fast-paced, high-stakes conclusion to Caragh M. O'Brien's Vault of Dreamers trilogy, Rosie travels to a derelict theme park to shut down dream mining once and for all.Driven by fear when Dean Berg kidnaps her family, Rosie Sinclair strikes out across the country to rescue them. When an elusive trail leads her to Grisly Valley, the contaminated ruin of a horror theme park, Rosie has to consider that Berg may once again be manipulating her every move to make her fearful, priming her for a final, lethal dream mining procedure. As Rosie struggles to outmaneuver Berg, she unearths the ultimate vault of dreamers and the hint of a consciousness more powerful and dangerous than any she's imagined before. Faced with unspeakable suffering and otherworldly beauty, Rosie must discover how to trust her mind, her friends, and reality itself. Propulsive and deeply speculative, The Keep of Ages concludes the Vault of Dreamers trilogy with stirring possibilities for what it means to be alive.