While Pete and his mother Jane try to determine the origins of their mysterious opponents, Myka and Claudia travel to Portland to stop a girl who can apparently vaporize anyone she hates with blasts of radiation.

As Sykes begins his end game, the agents discover that Helena is still alive... and teaching high school literature. Meanwhile, Jane reveals the full extent of her plan but one agent will lose their life carrying it out.

Pete and Myka race to stop Sykes from using his own cache of artifacts to destroy them and the Warehouse.

In the aftermath of the warehouse's destruction, the Warehouse team races against the clock to find a way to undo time itself and put right what went wrong. However, Artie finds himself facing a difficult decision when he is warned that saving the warehouse will unleash an even greater evil.