Day 6: 6:00 AM - 7:00 AM - S6-E1
Jack Bauer: Do you understand the difference between dying for something and dying for nothing? The only reason I fought so hard to stay alive in China was because I didn't want to die for nothing. Today, I can die for something.
Jack Bauer: I used to be in the military. Used to do field work for the CIA. I've been to some horrible places. I've seen some pretty terrible things. I don't think I've ever been this scared in my whole life.
Andre Drazen: If Plan A fails you go to Plan B, not Plan A recycled.
Jack Bauer: I've killed two people since midnight. I haven't slept in over 24 hours. So maybe you should be a little more afraid of me than you are now.
10:00 P.M.-11:00 P.M. - S1-E23
Sherry Palmer: You've got to be kidding.
Jack Bauer: I've never been more serious in my life.
Nina Myres: How did Jack sound?
George Mason: Alive.
Mason: Have you noticed, wherever you go there's a body count?
Mrs Palmer: They haven't told you? There has been an assassination threat.
David Palmer: Is that all? I thought it was something serious.
Chloe O'Brien: When we find the nerve gas and the alert level drops, we can have some chamomile tea and I'll tell you all my secrets, okay?
Jack Bauer: the only reason you're still concious is because I don't want to have to carry you.
Day 6: 10:00 AM - 11:00 AM - S6-E5
Graem Bauer: Actually, you're hurting me right now.
Jack Bauer: Trust me. I'm not.
Day 6: 9:00 AM - 10:00 AM - S6-E4
Bill Buchanan: We have to do better than we're doing, and we have to do it faster!
Day 6: 8:00 AM - 9:00 AM - S6-E3
Hamri Al-Assad: I do not work with my enemies.
Jack Bauer: You're working with one now.
Day 2: 5:00 A.M.-6:00 A.M. - S2-E22
Sherry Palmer: Who are you calling?
Jack Bauer: CTU. I am a sworn Federal agent, Mrs. Palmer. You just confessed to a federal crime.
Day 3: 2:00 P.M.-3:00 P.M. - S3-E2
[Jack has just shot Nina in the stomach, knocking her to the floor.]
Jack Bauer: You don't have any more useful information, do you, Nina?
Nina Meyers: [inching towards her gun.] I do...I do.
Jack Bauer: No, you don't. [Shoots Nina three more times.].
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.
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