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.

While Claudia tries to help a friend and gets unexpected help, Pete and Myka investigate an artifact that causes crowds to see certain individuals as monsters... and attack them.

While Pete and Claudia help Hugo Miller track down a bag of marbles at a boy's academy, Myka and Steve travel to New Orleans on the trail of another artifact while Artie meets with Brother Adrian.

While Pete and Myka investigate a series of artifact-related growth spurts, Artie reluctantly takes Steve and Claudia with him to track down Brother Adrian before he can steal more artifacts from the warehouse.

Pete, Myka, and Claudia set off to rescue their loved ones when Brother Adrian sends them deadly artifacts. Meanwhile, Mrs. Frederic and Steve travel to Rome and learn Adrian's dark secret.

The team have no time to mourn a fallen comrade as they go after the person responsible, the nemesis that has been stalking Artie since he used Magellan's Astrolabe to save the world.