Can the team capture Paracelsus before he achieves immortality on Warehouse 13? "The Truth Hurts" is the 20th episode of the show's fourth season.
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Warehouse 13 Season 4 Episode 20 Quotes

I'll use everything on the shelf to save Myka even you.

Pete

Mrs. Frederick: Paracelsus has the Warehouse.
Steve: And he has Claudia.
Artie: How?