10 Star Trek Moments You Never Saw Coming
7. Seska Is A Cardassian
Crewman Seska was never exactly the best example of the former Maquis fitting in aboard the USS Voyager. She was willful and headstrong, resentful of Janeway's command and frequently argued with Chakotay, whom she at least showed a modicum of respect for. The revelation that Seska was a traitor, trading technology with the Kazon, truly wasn't the greatest shock in the world.
Her actual heritage though, in being the fact that she was a Cardassian agent who was surgically altered to look Bajoran - that one was much more of a shock.
Seska had been planted aboard Chakotay's vessel by the Central Command, tasked with betraying him to her government when the time came. She is callous in how she speaks to both him and Janeway when her cover is blown, showing that she was no sleeper agent. This woman knew exactly what she was doing, who she was doing it for, and was not about to take orders from a Starfleet captain.
Before the audience has a chance to catch their breath after this reveal, she beams away onto a Kazon ship, becoming a true nemesis for the ship for the better part of the next two seasons.