Eddie McClintock

"Just when you think the writers can't raise the stakes, they threaten to destroy the entire world!" says Eddie McClintock with a laugh. He's talking about Syfy hit Warehouse 13's midseason premiere (Monday, 10/9c), which picks up with his artifact-hunting agent Pete and bestie-slash-partner Myka (Joanne Kelly) in a mad dash to find a cure for the sweating-sickness epidemic unleashed in October's cliffhanger.

Helping their cause is Buffy the Vampire Slayer veteran James Marsters, who guest stars as a professor with a specific — and very old — skill set that may help stop the global pandemic. While that arc sparks the action-adventure fun W13 is known for, the hour also takes a more serious turn as the team continues to deal with the fact that a possessed Artie (Saul Rubinek) has killed one of their own. "We have to honor the demise of Leena [Genelle Williams]," McClintock says, while promising that Season 4.5 won't be all death and destruction. "It's still Warehouse 13. We're gonna paint with all the same colors and just add a couple of different tones."

One bright spot: A nifty upcoming noir episode shot in black and white will feature Enrico Colantoni and Missi Pyle, and it will offer something special for the Pete-Myka devotees. "We get into some deep, deep relationship stuff," teases McClintock. "We find out how far Pete is willing to go for Myka."

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