Artie nods off at his desk and awakens to the click of a pair of handcuffs around his wrists. His captor is 22-year-old Claudia Donovan, the sister of a former student of Artie's who died 12 years ago when an experiment went wrong. Claudia blames Artie for her brother Joshua's death and she's come for Artie so he can make good on a promise he made to her long ago.
Pete, Myka and Mrs. Frederic use the Durational Spectrometer for clues on what happened to Artie. The device reveals images of him in handcuffs with Claudia. Pete, reading Artie's lips, makes out the name "Claudia Donovan." Meanwhile, in an underground lab at Minnesota University, Claudia explains to Artie that her brother didn't die - he got stuck during the teleport and has been visiting her and she wants Artie to help her bring him back. Artie notices Claudia is growing weaker and paler as air in the room grows more and more electrified creating chaos all around them. It culminates in an entity hovering before Artie - it's Joshua.
Back at Claudia's apartment, Pete and Myka notice a wealth of information on Rheticus, a 16th century mathematician and mapmaker with a keen interest in human teleportation. Amid their investigation, the two unexpectedly receive a call from Artie who assures them he's safe, but their excitement fades when he then orders them not to find him.
Mrs. Frederic surmises correctly that if Artie's with Claudia, he may be trying to recreate her brother's experiment so they need to figure out what went awry. Pete and Myka proceed to find secret compartments on all of the Rheticus objects in the box and they allude that Joshua probably never saw the rules hidden in the secret compartment on the compass. At the lab, Artie works frantically to save both Claudia and her brother but when Joshua appears again, he tells Artie he'll only be able to save one of them, leaving Artie with an impossible choice.
Pete and Myka burst in just in time and explain that all they need is the last rule on the compass. Artie hurriedly re-sets the artifacts and a light show explodes. Pete and Myka are left in an empty room - Artie, Claudia and Joshua are gone.
When the three find themselves in an interdimensional space, Artie explains to Joshua there's a hidden panel on the compass. When they find it, Claudia provides the correct combination and the light show begins anew. They each place a hand on the compass as the electrical field envelopes all three, transporting them back to present time and normal space in the lab.
All is well and calm at headquarters is restored...for now. Claudia, having breached Warehouse security, now knows an awful lot about the Warehouse and that, despite Artie's assertion to the contrary, could prove to be problematic.
Warehouse 13 is back for its final season, premiering Monday April 14 at 9/8c.
On a rainy day at the Warehouse, Pete accidentally triggers an artifact that transforms the team into two-dimensional diorama versions of themselves, and returns the Warehouse to its original, unstable design.
Saul Rubinek's talks about his family's way of celebrating the holidays and a spoiler on the series final season!