Some weird stuff goes down on the episode "Mild Mannered." Myka is clearly affected by a device in this still from it.
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Pete and Myke are after a unique device on the episode "Mild Mannered." It can turn people either good or evil.
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Pete is seen here from the episode "Mild Mannered." It focuses on an item that can make human beings good or evil.
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Warehouse 13 Season 2 Episode 2 Quotes

Artie: What?!
Pete: Cranky is kind of your natural state of being isn't it?
Artie: What Pleeeease?!

Leena: Now that is something I never expected to see.
Pete: Yeah, yeah, yeah, she must have found an artifact that makes her act like a girl.
Myka: mmmuaahh (makes face).