November 13, 2001: 1:00 AM-2:00 AM: In the second hour, Jack receives a desperate call from Richard Walsh (Michael O'Neill), who says he has uncovered key information about the Palmer investigation. On the home front, Kimberly is frightened by the increasingly erratic behavior of the young men who are holding her, and Teri's concern for her daughter grows as she and Janet's father (Richard Burgi) continue their search. Elsewhere, Presidential candidate David Palmer, unaware of the threat to his life, slips away to ask an old associate for help in dealing with a scandal that could derail his campaign.

November 20, 2001: 2:00 AM-3:00 AM: Jack asks York to stay with Teri at Janet's car; Mandy tries to fix her partner's error; Jack picks someone to trust; Palmer meets with a confidant (Zach Grenier) who assures him "I'll take care of it."

November 27, 2001: 3:00 A.M.-4:00 A.M.: Successes and setbacks mark the fourth episode of the countdown. Jamey is able to extract a clue that sends Jack back into the field, where he meets a helpful — and knowledgeable — police officer (Yolanda Ross). But Teri and York aren't so lucky when they're stopped for speeding by a cop (James MacDonald) who turns a deaf ear to their story about their missing daughters. Meanwhile, efforts at CTU headquarters are suddenly and severely hampered with the return of George Mason (Xander Berkeley), who tries to play on Nina's emotions as he fishes for Jack's whereabouts. Elsewhere, David Palmer (Dennis Haysbert) is made aware of the seriousness of the assassination threat.

December 11, 2001: 4:00 AM-5:00 AM: York finds his daughter, while Kim meets her captors' employer; Mason intercedes before Jack can question the cop killer; Palmer meets with Maureen Kingsley (Devika Parikh), who names her sources.

December 18, 2001: 5:00 A.M.-6:00 A.M.: Jack is reunited with Teri and informs her of the gravity of Kim's disappearance. In other plot developments, Jack needs Nina's help in identifying the mutilated body in the car trunk; and he also meets Alan York, Teri's companion for the past five hours, who bears some of Jack's stress while worrying about his own daughter, Janet. Meanwhile, Kim looks for some reciprocity as she assists Rick with a task assigned by Gaines; and Palmer learns that not all members of his team have been on the same page.

January 8, 2002: 6:00 AM-7:00 AM: A glitch in the conspirators' plans prompts a move by the CTU traitor, who is revealed in this episode. As day dawns, so does a new dynamic as Gaines (Michael Massee) takes his control over the situation to another level. Kim is his hostage and Jack his unwilling puppet, thanks to state-of-the-art surveillance that shows his every move. Teri, however, is able to gain the upper hand over York, whose impostor status is made known to Jack. Meanwhile, Rick (Daniel Bess) agrees to join Kim in an escape attempt; and Palmer decides to go public with Keith's secret, sparking controversy within the family.

January 15, 2002: 7:00 AM-8:00 AM: Jack's overall role in the conspirators' master plan becomes clear in this episode. As the Presidential-primary polls open, Sen. Palmer (Dennis Haysbert) makes a public appearance at a nuclear-power plant, where impostor photographer Martin Belkin (Rudolf Martin) passes a security check and is welcomed by a Palmer staff member (Jackie DeBatin). Gaines also directs Jack to the event, where he's surprised to find the same staffer, who happens to be an old high-school friend. Meanwhile at CTU, Jamey and Tony (Karina Arroyave, Carlos Bernard) each get startling news about Nina, forcing both to change their plans.

January 22, 2002: 8:00 AM-9:00 AM: Jack's explanation of the power-plant incident is met with skepticism from the Secret Service; Teri makes a sacrifice for Kim; Jack seeks leverage against the stonewalling Jamey.

February 5, 2002: 9:00 AM-10:00 AM: Another gripping episode begins with Jack on the lam and on his cell with Nina, who's trying to help him avoid police roadblocks. Teri finally gets in touch with Jack, only to be silenced when henchmen Rick and Eli return looking for Eli's missing cell phone. But Teri's able to keep the line open, providing the opportunity for Jack and Nina to listen in. At CTU, a new director (Tamara Tunie) takes the helm, and Tony finds a clue on Jamey's disk that reveals a wealthy contact whom Jack is interested in meeting. Meanwhile, Gaines is contacted by an unhappy employer.

February 12, 2002: 10:00 AM-11:00 AM: Nina hurries a psychological profile to help Jack with an interrogation as he takes a colleague of Gaines' for a wild ride; Eli punishes Rick; Gaines asks for more time from his employer, who mentions a contingency plan that doesn't involve him.

February 19, 2002: 11:00 AM-12:00 Noon: Jack closes in on Teri and Kim's location in this gripping hour. And while Jack insists on keeping it a one-man operation in the field, he calls on Nina for vital tech support. But she and Tony have problems of their own: Jack's replacement, Alberta Green, is now convinced they know where Jack is. Still believing Jack is a threat to Palmer, she pits Nina and Tony against each other in an attempt to force a confession. Meanwhile, Palmer's worst fears are realized when he learns just how far his backers will go to protect his candidacy.

February 26, 2002: 12:00 Noon-1:00 P.M.: Jack gives Rick a second chance; Teri and Kim are forced to deviate from Jack's plan; Green orders an interrogation of Jamey's mother (Christine Avila); Palmer gets surprising news from Maureen Kingsley.

March 5, 2002: 1:00 P.M.-2:00 P.M.: Jack is again separated from his family, and Nina thinks they may still be in danger; new information prompts CTU to advise Palmer to leave California ASAP; Keith has a change of heart after learning about Ferragamo.

March 12, 2002: 2:00 P.M.-3:00 P.M.: The motive behind the assassination conspiracy comes into focus as David Palmer has a face-to-face meeting with Jack Bauer. Convinced that Jack wants him dead, the senator cuts through red tape to meet the alleged suspect, seeking to put an end to the entire affair "right here, right now." But when the two men start to compare notes, they find they have a common acquaintance — someone who may be another target. They also realize why the conspirators have chosen this particular day for their actions. Meanwhile, Nina debriefs Teri and Kim at the CTU safe house.

March 19, 2002: 3:00 PM-4:00 PM: Pictures of suspected assassins are shown to Palmer's staff; Nina leaves the safe house after a tense moment with Teri; Jack and George Mason disagree over how to make the most of a lead.

March 26, 2002: 4:00 PM-5:00 PM: Keith Palmer (Vicellous Shannon) meets with Carl, who warns that "you're in way over your head." But that doesn't stop the troubled Keith from issuing a challenge to his father. Meanwhile, Tony learns that Teri and Kim's safety has been compromised, but Mason declines informing Jack of the situation. It's a calculated move to keep him focused on the business at hand as the Secret Service and CTU prepare for an operation that could give them an advantage over the conspirators. However, Jack does learn of Nina's telling exchange with Teri — and he's not happy about it.

April 2, 2002: 5:00 PM-6:00 PM: Following a new lead, Jack must work with a fellow CTU agent who harbors resentment toward him; Dr. Phil Parslow tries to diagnose Teri and explain their history; Kim meets Dan's brother (Edoardo Ballerini).

April 9, 2002: 6:00 PM-7:00 PM: Teri returns home in an effort to jog her memory; Mason and Jack investigate a lead obtained by Palmer; Dan's brother takes matters into his own hands after learning of Dan's death.

April 16, 2002: 7:00 PM-8:00 PM: Dennis Hopper joins the series for the season's remaining five episodes as the mastermind behind the conspiracy. His identity and motives for seeking vengeance against David Palmer and the Bauer family are revealed during this taut episode, in which Jack continues searching for clues as to why the Drazens had planned to cut the power in an apparently deserted area. Lou Diamond Phillips plays a man named DeSalvo who has some answers. Meanwhile, Mason heads back to interrogate Alexis Drazen; Rick tells Kim what to tell the cops; and the country responds to the press conference in which Palmer talked about Keith.

April 23, 2002: 8:00 PM-9:00 PM: Mason orders backup for Jack; Victor Drazen and Jack debate responsibility for their respective actions; Teri is brought back to CTU; Kim stands her ground against Melanie.

May 7, 2002: 9:00 PM-10:00 PM: Victor offers a deal to the Feds, and Palmer makes his own deal in order to help Jack after learning Victor is alive; CTU learns the latest on Kim.

May 14, 2002: 10:00 PM-11:00 PM: Jack is forced to do the Drazens' bidding; CTU uncovers a lead on a second traitor; Kim witnesses the reunion of Victor and Alexis; the Palmers make plans for the future.

May 21, 2002: 11:00 P.M.-12:00 A.M.: The episode finds Sherry Palmer distressed about the role she's been made to play in the media ruse that was necessary to buy time for Jack. When Jack arrives at the perimeter of the Drazens' location, a war of wills ensues. However, a phone conversation gives Jack information that helps identify the second CTU traitor, enabling him to warn Nina. And as time grows short for the Drazens to make their escape, Andre and Victor disagree about whether to follow through on at least one part of their plan.