Day 4: 6:00 P.M.-7:00 P.M. - S4-E12
Plot hole: When Conlon searches for Paul in the dark he holds his gun and the flashlight in his crossed hands. You can see how the light of the flashlight brightens the side of the gun. But the cone of light on the wall is a full round circle. (00:37:55)
Answer: According to Jack in season 5, Nina was "deep cover" before the pair ever met, so it's safe to assume she was recruited before she joined CTU. As for what her primary mission was, who knows? Perhaps it was to gather sensitive intel and pass it on to her superiors. Given that she worked for an intelligence agency, it's not a stretch. Or perhaps we may find out in season seven.
Cubs Fan ★