Monder is a Tromindox so dangerous he was banished to a labyrinth that exists out of time. The portal that sent him there has been severed in two, never to be made whole or used again. But when Monder gains possession of one of the halves, the Silverwoods are faced with the prospect that he might escape. Henry Silverwood, whose Guild talents are growing exponentially, is taken when Helen is faced with an impossible choice: give him up, or watch him be eaten. Meanwhile, the Tromindox are evolving - and the Silverwoods do not have the advantages in hunting them that they once had. Now, the Silverwoods must make sense of Monder's increasing power in the time world, find Henry, and avoid extinction themselves.