As the nation remains vulnerable, Jack Bauer endures the worsening pathogen pain; the FBI deals with recent deadly developments, while matters involving key players take this day in an unexpected direction.

Patricia Eames gets a phone call at her home from her co-worker Matt; she's Jonas Hodges' favorite attorney, and he's calling her in to represent him. As she opens her front door to leave, she's ambushed by a man hidden behind a mask. He gasses her, and then gives her a lethal injection. Just before she dies, she sees a woman who seems to be her exact double. The double, Cara Bowden, steals Patricia's glasses. The man uses a device to scan Patricia's thumbprint, and transplant it to Cara's hand in the form of a thin plastic coating.

At the FBI, Galvez is ID’ed from a Starkwood security camera; a four-block area is locked down. Within that perimeter Tony shoots himself in the side, and then tells Galvez via phone to stay put: the canister Galvez stole for Tony is worth a lot of money to the people Tony's working for. The FBI arrives to find Tony shot and Moss dead. He claims they were ambushed. Later he calls Galvez, and warns him of the FBI's movements. Tony advises him to find a large store or warehouse in the area he can lure the FBI into. They can then blow up the building and the agents within. Back at the FBI, Kim Bauer says goodbye to Agent Walker. Her father won't agree to the treatment, and she knows there's no point in trying to change her father's mind once it's made up. She's just happy they got to say some of the things they wanted to say to each other. Just then Walker gets the call informing her that Moss is dead, which leaves her as the ranking agent in charge. Walker is stunned, but pulls herself together and begins issuing orders, showing no trace of emotion. She cuts Janis off when she tries to offer condolences. It’s time to take care of business. Meanwhile, Jack's having trouble with his debriefing; his memory is starting to fade due to the bioweapon's effects. He's distracted by the sight of Walker addressing a SWAT team, and goes to investigate. When he learns that the bioweapon is still out there, and that Moss is dead, he insists on going along with Walker. Jack promises to stand down if his condition compromises the operation in any way. She continues to protest, but he cuts her off. He's going, and that's final.

At the White House, President Taylor worries about Hodges' claim to be a small cog in a much larger machine. She wants him interrogated by the FBI. Olivia says he'll want some kind of deal in exchange for information. The President knows, but promises not to make any deals with the monster who is responsible for Roger's death. Cara, disguised as Patricia, arrives at the White House brig to see Hodges, who knows exactly who she is: "You're a little taller than her, but it's a good look for you." She tells him that his actions have put everybody in a very difficult position. He shouldn't have worried about Senator Mayer's subpoenas; Hodges and Starkwood would have been taken care of. The bioweapon wasn't for his personal use. The consensus is that Hodges has had a psychotic break. He's exposed himself, and there's concern that he'll expose the others. Hodges says he doesn't even know who the others are, but Cara says he knows enough to be dangerous. She threatens his family, but promises their safety if he does "the right thing." She slips him a capsule that will induce cardiac arrest without leaving a trace. It'll look like a natural death. Without Hodges to prosecute, the case against him and Starkwood will be difficult if not impossible, and Starkwood's legacy will be preserved. Olivia arrives; her time alone with her "client" is over. He's being moved. Cara calls Alan Wilson, and tells him she hopes his impending interrogation will pressure him to "resolve" the situation. He asks if she's heard from Tony, and she says yes, and he'll have the canister secured soon. Wilson says that Tony's her guy, and he'd better not screw up. Cara has faith that he'll come through.

Tony finds a secluded area, and takes a call from Galvez. He's found a building; Tony tells him he's got less than twenty minutes to rig it with C-4. Jack and Walker are in a chopper heading for the scene. Jack tries to advise her on how to cope with the pain of losing a partner, but she doesn't want to hear it. They arrive at Tony's location. Jack realizes Tony's story about the ambush doesn't quite check out: most of the bullet holes are from a .45 caliber gun, but Tony was shot with a 9mm. Unfortunately Jack comes to the wrong conclusion, that Galvez must have had somebody else helping him. From a taxi Kim calls her husband Stephen, and says she's coming home. He asks if she at least told Jack about his granddaughter, and we see Kim and Stephen's 14-month-old, Teri, playing in her crib. She says no; that would have just made things harder for her father. She'll be on the 7:10am flight and be home by nine.

Walker is concerned that the sweep isn't happening fast enough; Royce reports that they're being slowed by civilians who are protesting their homes being searched without a warrant. Walker orders any civilians who interfere arrested so that the area can be cleared quickly. Jack begins to shake again; he finds a private area where he is just barely able to administer himself his anti-seizure medication. Tony tries to persuade him to go back to the FBI, but Jack's here to support Walker. Just then a static-y transmission comes in: it's Galvez pretending to be Agent Stoller, who he’s just killed. He claims to have a confirmed visual on the suspect and the canister entering an abandoned apartment building. Jack asks if there was anyone with Galvez. The reply is no, which troubles Jack. As Walker and the FBI team prepare to move out, Jack stays behind to monitor operations. Galvez, as Stoller, lures the FBI up to the second floor of the building. Jack gets a call from Agent Mizelli, who was conducting his debriefing earlier, to try to clear up a discrepancy: is Jack sure that Tony's source on the White House attack was named Vincent Cardiff? Jack's sure, even with his condition. Something catches Jack's attention, and he tells Mizelli he'll have to call him back. As Walker and the other agents go deeper into the building, Jack realizes that the agent's transponders are showing that Stoller isn't in the building with the rest of the team. He radios Walker and shouts to get out: it's a trap! As they begin to retreat, Galvez, hearing this exchange, sets off the detonator. As confused reports come in of agents being down and requests come in for assistance, Jack takes command and demands that the perimeter teams hold their positions. This was an attempt to draw them off their line; any hole in the cordon, and they lose the canister. Agent Walker is missing. Jack rushes over to the site, Tony in tow.

As Hodges is transported to the FBI, he notices a tattoo on the arm of one of the Marines who have him in custody. He recognizes the tattoo: the Marine served in Pakistan, side by side with Starkwood operatives. Hodges asks how he'd rate their professionalism and performance under fire. The Marine tells him they were good men, well trained. Hodges, moved, tells him he just made his day. Hodges then retrieves the capsule. He regards it for a moment, and then swallows it. He goes into cardiac arrest.

Jack and Tony enter the building. Tony rendezvous with Galvez, who is disguised in Stoller's uniform. Galvez confirms that he still has the canister, and then dips his hands in the blood of an agent killed in the blast, smearing it all over his face. Meanwhile, Jack finds Walker alive and well; her radio was knocked out, and she's been tending to a severely wounded agent. Walker realizes that whoever did this knew their sweep pattern. Jack calls Mizelli back, and Mizelli tells him that Vincent Cardiff didn't expire as a result of Tony's interrogation, like Tony said. Cardiff was arrested by Customs an hour ago, trying to sneak over the border into Canada. He shows no signs of any physical abuse whatsoever. Jack confronts Tony... who is just bundling Galvez into an ambulance. As the ambulance drives away, Jack draws a gun on Tony: he said that if Tony ever lied to him, he'd take him down himself. Tony tries to talk his way out of it, but Jack's not buying it. Suddenly Jack begins to spasm again. He drops to his knees, shaking. He tries to find his hypo kit, but it turns out that Tony has stolen it from him. Tony takes Jack's gun, and says he never wanted to hurt Jack. Just as it looks like Tony's about to shoot Jack, two medical techs run up. Tony hides the gun, and shouts to them that Jack needs help. As Tony walks away, Jack tries to shout a warning, but he can't speak. As the ambulance carrying Galvez is waved through the roadblock, Galvez suddenly stabs one med-tech in the throat, and then takes the driver hostage at knifepoint before he can send a message for help.