Three years have elapsed since the events of Day Two. A van unloads a corpse outside the Los Angeles Health Unit. The body carries a virulent infection. Tony, now head of CTU, discovers it's an attempt at blackmail: the US government must r…

A rift forms between Jack and Chase, sparked by Chase's involvement with Kim. Separately, their raid on a dilapidated house yields a potential clue to the virus’s location. Linda ends her relationship with Kyle upon discovering his plans to…

Kyle’s disappearance prompts a parallel search by both Jack and Hector, while Chase is sidelined from active duty at CTU. Meanwhile, Wayne and Palmer clash over the ramifications of Anne’s history, and Ramon unexpectedly neutralizes an …

The weight of personal and professional demands presses heavily on Michelle as she assumes leadership of CTU following Tony’s injury. Meanwhile, Kyle and Linda fall into the hands of Hector’s adversaries. A clandestine conversation …

Jack’s attempt to free Ramon from prison descends into chaos when they are caught in the crossfire of a riot and captured by fellow inmates. Chloe inadvertently discovers Jack's dependence on drugs and is compelled to reveal his secret …

Evading the authorities proves a difficult task for Jack and Ramon, while Palmer is forced to halt the debate proceedings due to the prison break. Kim inadvertently discovers Gael’s clandestine communications, but she is unable to deliv…

Ramon has taken Jack captive aboard a flight to Mexico. His intention is to kill Jack, but Jack manages to restrain him until the aircraft lands. It is then that Ramon discovers Jack and Hector are collaborating on an escape from prison. …

Palmer and Chappelle discuss a message from Jack detailing his clandestine activities with the Salazars. Separately, Hector attempts to persuade Ramon that dealing with Bauer is the only path to acquiring the virus. In a private exchang…

Palmer successfully navigates the press to rehabilitate Anne’s reputation, only to discover a fresh complication when his most significant campaign donor reveals a shocking secret about Wayne. Kim and Michelle grow concerned about Tony's…

Claudia breaks Chase free from his captors, though the liberation comes at a steep cost. Meanwhile, Wayne seeks out Julia, and Palmer calls upon Sherry for assistance in their confrontation with Milliken. Jack and Ramon begin to for…

Jack compels Nina into an alliance to secure the virus from Amador. Palmer meets with Sherry, persuading her to assist him in matters concerning Milliken. Chase stays in Mexico to aid in the retrieval of the virus. Ramon and Hec…

The situation erupts as Jack, Ramon, Nina, and Chase converge on the virus. However, the unfolding events take a sharp turn when Amador executes a sudden maneuver. Kim’s doubts about Chloe deepen as inconsistencies emerge in her account …

Jack and Chase questioned Nina, but the situation shifted dramatically when she began disrupting the CTU's computer systems. Chappelle placed Chloe under guard after she refused to answer questions about the infant, but he was compelled…

Tony pressed Nina for information regarding Alvers’ whereabouts, while Chappelle instructed Jack to submit to a medical examination given his recent drug use. Kim and Chase spoke about the impending arrival of their child. Palmer co…

Chappelle considered withdrawing Jack from the case, citing the killing of a witness, but Jack’s persuasive argument convinced him to wait. A new clue regarding Amador’s location had emerged. Amador and Alvers met with the individual poi…

Driven by the hope of uncovering the perpetrator behind the viral attack, Jack and Chase pursue Amador relentlessly. Meanwhile, Michelle finds herself confronting a violent mob as the hotel is placed under quarantine. In a calculated…

Saunders escalates his pressure on the President, compelling Palmer into an unusual press conference. He then issues an order for the elimination of the CTU agent capable of tracking him. Jack discovers a woman who might lead him to Saun…

Time is running out for Jack and Chase as they pursue Saunders, racing to apprehend him before the deadline arrives. Meanwhile, Chappelle is formulating a plan for escape. News of a potentially infected hotel guest evading Michelle sets…

Reluctantly, Jack agrees to collaborate with Kim on a covert operation, one that offers the potential for an edge against Saunders. Palmer briefs his cabinet on the escalating crisis, as Saunders issues yet another demand. Chase trac…

Jack tries to manipulate Saunders by using his daughter as a bargaining chip in the struggle for control of the virus, while Palmer navigates the growing hostility of the press. Michelle receives the outcome of her test, and Adam discov…

Tony labored to secure Jane's release from the confines of CTU, racing against the possibility of Saunders harming Michelle. Meanwhile, Chloe and Jack grew wary of his actions, their suspicions steadily rising. Elsewhere, Sherry arrange…

As the deadline for the hostage exchange approached, tension escalated between Jack and Tony. Meanwhile, Keeler summoned Palmer and demanded his resignation. Simultaneously, Wayne initiated a clandestine operation targeting Sherry.

Determined to compel Saunders to reveal the whereabouts of the vanished vials, Jack takes increasingly risky measures. Meanwhile, Sherry meets with David to negotiate her demands, as Wayne secretly enters her residence in search of the …

Faced with the virus, Jack and Chase are confronted with a difficult and profound sacrifice. Tony offers Jack a final measure of assistance before his arrest, while a grieving survivor seeks retribution against Saunders. In the afte…