Pete and Myka trace two cases of a strange rusting disease to a factory run by a shady character named Siskel, and uncover links to an explosion at a museum. Meanwhile, Steve and Claudia try to get Steve off the metronome, while Artie deals with Helena, Leena, and Mrs. Frederic about the astrolabe and Brother Adrian.

After discovering the truth about their situation, the agents gather at the Warehouse and set out to find the person responsible for the Warehouse thefts and the attacks on their loved ones... before the responsible party endangers the world.

Unable to find where H.G. Wells hid the astrolabe, a criminally insane Artie threatens to unleash a plague upon the entire world if it is not given back to him. The Warehouse agents race against time to stop him.