These are the Previously on 24 segments for Season 1. Names in bold were pictured in the title cards.
Beginning with "Day 1: 7:00am-8:00am," a narration from Jack Bauer is included prior to the Previously on 24 segment. The narration was altered slightly twice over the course of the season. For reasons unspecified, both Region 1 DVD releases of season 1 omit the Previously on 24 segment and go straight from the narration to the start of the episode. This segment is also omitted from the episodes made available for streaming on Amazon's Prime / Instant Video service.
Jack notices that Kim Bauer snuck out of the house so Teri states that she is grounded for two months. Meanwhile Kim and Janet York arrive at Paladio Furniture.
Teri Bauer tells Jack that Kim got an e-mail from Janet York, and that she is going with Alan York to find them. Teri asks Jack to come with her, but he cannot.
Jack Bauer is told by Richard Walsh that there is a mole within CTU. Walsh gives Jack a card that has data on it and that it will identify the mole. Jamey matches the card to Nina Myers.
Teri Bauer asks a homeless woman about Kim and Janet and she tells Teri that one of the girls (Janet, but she does not know this) was hit by a car and that she did not look well.
Jack Bauer discovers a mutilated body in the trunk of a car and tells Mason to trust him because it will look very bad if something happens to Palmer that night.
SenatorDavid Palmer asks Carl about the Ferragamo situation in which he states that it doesn't make a difference as long as he is protected . Though Palmer claims that it does make a difference if someone innocent is murdered.
Nina Myers is questioned by Alberta Green of Jack's whereabouts but lies by saying that she hasn't talked to him since this morning. Though Alberta claims that she doesn't believe her.
Nina Myers tells Tony Almeida that after Jamey's betrayal towards CTU they don't know who to trust.
Jack Bauer interrogates Kevin Carroll about the whereabouts of his wife and daughter. Then he tells him that as soon as he knows that his family is safe he will let him go.
Andre Drazen meets Ira Gaines and tells him he is pulling the plug on him, as he was supposed to frame Jack for the murder of David Palmer. He gives Gaines 30 minutes to find Bauer.
Nina tells Jack that they found Gaines' inside person, Jamey Farrell. She says that she didn't mean any of this to happen, then she tries to kill herself. Tony is informed by the clinic that she didn't make it.
SenatorDavid Palmer meets Carl Webb to tell him that Maureen Kingsley is going to accuse his son of murder. Maureen tells Palmer her source is George Ferragamo. Palmer calls Ferragamo to warn him he is under threat, then Mike tells David his office burnt down. Palmer says it was murder.
Jack Bauer holds Kevin Carroll at gunpoint while they drive into Gaines' compound. He tells Nina he is on his way in, and she warns him not to. He hugs Teri and Kim, then phones Alberta Green to say he has located the people behind the Palmer hit. Jack pulls a gun on Rick, who says he is helping them because he got Kim into it. Jack asks Kim if she trusts him. Jack's van crashes through the perimeter fence as Gaines and his men chase. Jack tells Teri and Kim to follow the creek bed to an old abandoned water tower. Rick is shot through the arm. Jack fires and blows up the van.
Teri Bauer asks Nina why they are being taken to a safe house. Nina tells them it is the best environment for them as they make themselves at home. Kim finds out that Teri is pregnant. Teri then works out that when she was separated from Jack, Nina was seeing him.
Andre Drazen is talking to his brother, who tells him Jovan and Mishko have their targets in sight. He says that Palmer won't be leaving LA, and gives his word that he will be dead by midnight.
Palmer then approaches Chappelle and tells him to reinstate Jack Bauer to his previous position. Jack says that anyone who can connect Palmer and himself must also be able to find Robert Ellis. Ellis asks what they are doing together, and Palmer tells him the three of them are on someone's list. As Jack is talking to Ellis, he is strangled by an unseen assailant.
Kim Bauer phones Rick Allen to tell him the safe house has been attacked and the agents are dead. She says her mother is gone, and she is coming to his place.
Teri Bauer is in the car with Tanya, who says she has never met anyone with amnesia before. Henry Martin then asks Teri if Dr Parslow will be joining her. Phil asks if she remembers him, and then tells her they will figure out what is going on.
Jack Bauer briefs Elizabeth and tells her he wants her to plant a tracking device on him. He watches as Alexis enters the hotel room, and Elizabeth stabs him. He bursts into the room and attempts to resuscitate Drazen. Nina then hands him Alexis' ringing phone. Jack 'takes a chance' and answers the phone, being told to meet in 45 minutes with a mystery contact.
SenatorDavid Palmer is celebrating his victory. Mike Novick tells him being president is what he needs - it doesn't matter if his marriage doesn't help him. Mike tells him he can have whatever he wants, as we see Patty Brooks giving him a massage. Palmer is massaged by Patty Brooks.
Jack Bauer explains to George Mason that he is in a prison housing Victor Drazen, the man he took out 2 years ago. Men shoot at him and Jack gives Victor up to Andre.
Jack asks Victor Drazen when his suffering will end, and Victor says when all his enemies are dead. Just before shooting Jack, Jack asks if he ever wants to see his son Alexis again. He says he knows where he is, and Victor's men put Jack into the van.
Kim Bauer is released from prison by Sam Krugman. He tells her that her mother is waiting at CTU, and Teri asks how Kim ended up in jail. A van smashes into Kim's police car, Krugman is shot and men drag her away at gunpoint.
Jack tells SenatorDavid Palmer and Sherry Palmer that the world needs to think that David is dead. Sherry asks why, and Palmer says its because Drazen has Kim hostage.