Spoilers for this episode.
Marcos Al-Zacar remains inside the hospital's hyperbaric chamber, working to bypass the interference that stopped his suicide vest. CTU estimates that cutting into the chamber will take too long, and Jack Bauer wants him alive. Chloe finds his family history, including his father's detention and subsequent suicide, and identifies his mother as a possible way to reach him. Hastings sends Cole to bring her to the hospital while radiation detectors are deployed around Manhattan.
Cole and Dana return to CTU after their unexplained absence, and Hastings warns that their careers are in danger. Dana loses her senior position to Chloe and receives a call from Kevin's probation officer, who is tracing his contact with her. Meanwhile, Samir's men prepare to move the nuclear rods past the city's defences. At the hospital, Marcos's mother appeals to him, but her plea alone does not persuade him to surrender.
Jack threatens to expose Marcos's mother to the consequences of the blast, forcing Marcos to come out. Marcos rearms the vest before emerging. The terrorists activate its fail-safe, and Jack cannot disarm it in time. Marcos identifies Tarin as part of the conspiracy before the explosion kills him. The information turns CTU's attention toward the man who has been close to Hassan and Kayla, while the nuclear material remains outside the team's control.