With the fate of the world in their hands, Pete and Myka's only hope of finding a cure to the Sweating Sickness is a drunken history professor. Meanwhile, Steven and Claudia enter Artie's subconscious in an attempt to bring him out of his coma before he fades away for good.

Pete, Myka, and Charlotte must track down Sutton, the only man who knows where they can find Paracelsus and exchange the Philosopher's Stone for the stele that will free Claudia from her bronze imprisonment... before she disintegrates.

Pete and Myka capture Paracelsus but not before he makes himself immortal. When Myka's cancer becomes worse, Pete must make a deal with Paracelsus to cure his partner. Meanwhile, Claudia receives some startling news from Artie.