Jack contacts Mike and asks for a secret meeting in hopes of gathering evidence against Walt.

Martha begs Aaron for help, while a desperate Walt tries to force Logan to aid him in his complicity with the terrorists.

Buchanan butts heads with Lynn over a decision to violate the president's orders, while the Russians attempt to escape with the nerve gas.

Lynn orders Curtis to take Jack into custody for violating presidential orders, but Jack breaks away from Curtis when Nathanson contacts him through Audrey and offers information on the location of the nerve gas.

Lynn begins to unleash on his coworkers as he discovers that they may be working against him to aid Jack.

The head of the terrorists makes a demand on Logan, and Martha takes a dangerous step to get her husband's attention.

Jack and Wayne locate a recording that definitively proves Logan's involvement in the terrorist conspiracy, but Henderson corners them in the hopes of destroying the incriminating tape.

Logan tries to cover his tracks by issuing a warrant for Jack's arrest.

Audrey contacts her father for help, while Chloe gives her cover while helping Jack evade CTU.

Bierko escapes from the transport taking him to Division and uses his last canister of nerve gas for a surprise strike. Jack is forced to work with Henderson to find Bierko, but Henderson wants something in return. Logan takes drastic steps to deal with Aaron when he won't go along with the cover-up.

Jack and former terrorist leader turned peacemaker, Hamri Al-Assad, track a suspicious man to a self-storage facility.

The President meets with a known terrorist, while Jack searches for Morris, Fayed seeks a trigger, and Tom Lennox makes a choice.

Jack's search takes him to the Russian Consulate, while the Vice President contemplates a sweeping executive order.

CTU's satellite tracking system is compromised as a bomb-carrying drone heads toward an unknown city. Meanwhile, US forces prepare for a nuclear retaliation on the Middle East.

To find the remaining suitcase bombs, both Jack and the President set up bluffs.

Jack rushes toward his nephew and his oldest antagonist, as a Chinese sub and F-18s race for the same destination. Chloe faints. Can Jack find any peace?

Buchanan takes Jack to "CTU", a secret hideout where he and Chloe had been working with Tony to uncover the conspiracy within the US government. Tony had been undercover with the terrorists aiding Juma to discover the moles. Jack agrees to help get Tony back in play by joining Emerson's crew himself.

Taylor is forced to meet with Matobo to inform him that she may be required to withdraw her forces from Sangala to protect American lives. Her Chief of Staff Ethan Kanin agrees with this decision, but Taylor is not yet convinced.

Henry meets with Samantha, Roger's former girlfriend, who tells him that Roger was indeed murdered and provides him with proof.

After eight hellacious hours of this terrible day have elapsed, the country remains on edge. President Taylor struggles with the painful circumstances facing the First Family, including her daughter Olivia (guest star Sprague Grayden). Meanwhile, a huffy Chloe faces-off against paranoid FBI Agent Janis Gold, while Jack and Agent Walker track leads through Washington, D.C. to eliminate the threat of another ruthless terror attack

As the nation remains vulnerable, Jack Bauer endures the worsening pathogen pain. The FBI deals with recent deadly developments while matters involving key players takes this day into a unexpected direction.

Jack Bauer is forced to help Tony escape from custody, only to find Tony plans to use Jack to reconstitute the pathogen. Aaron Pierce and Ethan Kanin work together and discover Olivia's role in Hodges' murder. Kim Bauer takes down her captors, and works with Renee Walker to find her father.

Jack Bauer becomes further involved in preventing an assassination attempt on visiting president Omar Hassan. As the crisis continues to escalate, the crew at the newly upgraded CTU is challenged by some unexpected complicated circumstances. Meanwhile, tensions run high when an explosive event jeopardizes international security.

President Taylor pressures CTU for progress while Jack's perilous plan has operatives panicked. As the scope of the looming threat expands, the dynamic at CTU changes and the ongoing crisis worsens.

The clock races into the middle of the night when the threat of a devastating nuclear attack accelerates as Jack tracks an informed terror suspect who has an explosive strategy. Back at CTU, a key player grapples with being demoted, and the day takes an unexpected stressful turn when pesky parole officer Bill Prady enters the picture.

As the country reels from the day’s devastating events, stalwart President Taylor attempts to resuscitate the peace agreement, the cornerstone of her administration. Much to her dismay, she is forced to solicit the services of disgraced former President Logan. Meanwhile, Jack Bauer makes an unprecedented emotional move that triggers the unthinkable, and back at CTU, Chloe is charged with new responsibilities.

As the clock ticks toward the climactic series finale, three hours remain and a ruthless Jack Bauer is on an unwavering mission to uncover the truth, which only complicates circumstances for President Taylor as she prepares for a signing ceremony. Meanwhile, President Logan comes face-to-face with a formidable foe, and Chloe leads CTU on a high-stakes collision course with Jack Bauer.

Jack and Chloe are on the trail of a hacker who might lead them to whoever is behind an assassination attempt on President Heller... but Kate is hot on Jack's trail.

As the smoke clears after the devastating events of the first five hours, tensions between President Heller and Prime Minister Davies boil over, and one of them decides to take matters into his own hands. In the meantime, Jack proposes a plan to locate Margot by using someone unexpected as his unsuspecting bait. Back at the CIA in London, Jordan raises suspicions about Kate's husband.

Audrey pursues diplomatic channels to try to prevent a full-scale war. Meanwhile, Jack Bauer leads Kate Morgan and Mark Boudreau on a mission to locate their target before it's too late and the world is changed forever.