It's been a year since Jack lost his wife, and the emotional toll includes estrangement from his daughter Kim, who is now a live-in au pair for a troubled family. Jack is no longer with CTU, and no longer interested in that line of work - until he's summoned directly by President Palmer. The situation: terrorists have planted a nuclear device somewhere in Los Angeles and plan to detonate it within 24 hours.

Jack tries to undermine Eddie's mission to bomb CTU while George investigates intel leading him to the site of the nuclear bomb's construction and Kim tries to make contact with her father by heading for CTU headquarters.