Andromeda

The Opposites of Attraction (5x15)

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While Harper develops a way to save the Seefra system from its impending doom, a spy has slipped on board the Andromeda. Dylan, Rhade, and Trance all feel that someone who should not be aboard is, but cannot confirm their suspicions. Things turn south when the spy attacks Beka by opening a portal to open space inside the ship.