Season synopsis
Contains spoilers for this season and earlier seasons.
Eighteen months after the first season, Jack Bauer has left CTU following Teri's death, but President David Palmer calls him back when intelligence warns that a nuclear bomb is headed for Los Angeles. Jack works with CTU and Kate Warner, who suspects her sister Marie's fiancé is tied to the threat. Kim, meanwhile, is on the run after rescuing a young girl from an abusive father, and Jack worries about her safety while trying to reconnect with her.
The bomb is found and Jack flies it away from the city, where it detonates in the desert; CTU director George Mason, fatally exposed to radiation, takes the aircraft in Jack's place. The crisis then shifts to a recording that appears to link three Middle Eastern countries to the attack. Palmer refuses to order retaliatory strikes without proof, so cabinet members invoke the Twenty-fifth Amendment and Vice President James Prescott assumes the presidency. Jack, Tony Almeida and Michelle Dessler investigate whether the recording is genuine.
Their investigation uncovers an oil consortium's scheme to fake the evidence and profit from war. Palmer's ex-wife Sherry, herself drawn into the conspiracy, risks her life to obtain a confession from Peter Kingsley. The evidence stops the strikes, and Palmer is restored to office, though he dismisses chief of staff Mike Novick for failing to support him. The nuclear threat ends without a citywide detonation, but Mandy attacks Palmer with a biological agent during his public appearance. He collapses, leaving his survival unresolved at the season's close.