[1] The show stars Eddie McClintock, Joanne Kelly, Saul Rubinek, Allison Scagliotti, Genelle Williams and Aaron Ashmore.

[6] In April 2013, it was announced that Anthony Head had been cast as a villain named Paracelsus, and would appear in the final three episodes of the fourth season.

With matters so desperate, Pete, Myka, Artie, Leena, and Claudia must decide whether to knowingly use a dangerous artifact for their gain - at the risk of deadly consequences.

Pete and Myka are sent to Philadelphia to find an artifact that is the cause of strange hallucinations - people fear monsters, but only humans are killed when attacked.

Artie, under the influence of Bobby Jones' Golf Clubs, accidentally mentions, in not so many words, that he saved the world, but that no one will ever know, which worries Leena, as his rage is something she has never seen before.

Pete and Myka are sent to retrieve World War II dog tags from a woman who uses them to wish away a hockey player's injuries so he might have a successful season.

Meanwhile, an influential medical company executive has created a (seemingly) new artifact-related drug with the ability to increase people's height.

Peter has a one-night stand with Deb Stanley, an executive from the medical company who deduces the artifacts' existence and tells her boss, who in turn pressures a senator and forces the intervention of the Regents.

Deb is told the truth, thanks to Pete's good feelings about her, she helps mislead her boss, and she's offered the possibility to become a Regent in the future.

The culprit turns out to be a boxer and steelworker, Cody Bell, who has shrapnel from Spartan armor lodged next to his heart from his time serving overseas in the Marines.

The two reconcile and Steve is finally released when he destroys the Metronome in order to save his mother's life, an act of pure love.

They find out that Artie wants to use the blade to break the Chinese orchid container, which would release a deadly disease - the English Sweating sickness - into the world.

Mrs. Frederic, Pete, and Myka look for an artifact that can bring The Chinese Orchid back to life and stop the "sweating sickness" pandemic overtaking the world.

They track down a professor at Columbia University (James Marsters) who is the foremost expert on the Count and enlist his help in recovering the ring from the Catacombs of Paris.

As Pete and Myka grab the ring from the tomb, the Count steals a diamond, triggering booby traps set by Marie Antoinette.

Back in the tomb Charlotte Dupres claims that the professor is her husband of many centuries and realizes that the entire 'poison dart death scene' was a fake, one of many she ascribes to the Count, whom she seems to know very well.

Artifacts: The Chinese Orchid, most giant diamond from Marie Antoinette's infamous necklace, Count of St. Germain's ring, Sigmund Freud's desk clock The Regents forgive Artie and give him Leena's video statement.

Meanwhile, back at the Warehouse, Myka and Steve are trying to keep an eye on Artie trying to work his way through a list of Leena's duties, including placing new artifacts.

Meanwhile, Steve, Claudia, and Artie search for a thief stealing classic cars from locked rooms - by driving them through solid walls.

Pete and Myka head to Las Vegas to check out glowing orange bodies falling from the sky and get caught in a feud between two show magicians.

Meanwhile Claudia and Steve are on their way to London to investigate a few long-shot horses putting their jockeys into comas after one in a million wins.

Pete, Myka, and Steve head to the scene of a recent prison break where they discover the outer wall was melted clean through by what appears to be molten lava.

After a DA dies in his driveway, Pete and Myka must figure out what's going on at a high-class and expensive gated community where residents are being affected by a mysterious versatile supernatural artifact.

Meanwhile, Artie and Claudia team up to investigate a possible artifact after Nick (Josh Blaylock), a homeless 15-year-old boy, suddenly has moments when he becomes a mathematical genius followed by having dangerous, life-threatening seizures.

Pete, Myka, and Charlotte head to Luxembourg on the trail of Paracelsus and Nick, who have stolen the artifact which operates Warehouse 13's Bronzer so that they can debronze Claudia.