Jack is back, this time in New York City spending time with his granddaughter. However, when a former contact comes to him with vital information on an upcoming terrorist assassination attempt, Jack has no choice but to become involved and take the man to CTU. But to get to CTU, they first need to survive a whole bunch of terrorists all trying to kill them. Meanwhile, Chloe struggles to settle in at her new position at the upgraded CTU, and President Allison Taylor negotiates with Middle Eastern leader Omar Hassan over weapons inspections... unaware that Hassan is the assassins' target. Also, a journalist named Meredith Reed is suspected to have direct ties with the on-going terrorist crisis.

For the first time in New York City, Jack Bauer is reluctantly drawn into action as President Allison Taylor negotiates plans for international security with Middle Eastern leader Omar Hassan. As the 8th day keeps unfolding, we learn that CTU, now upgraded and operated by M.B.A.-schooled Brian Hastings, still has Chloe O'Brian, but also expert analyst Dana Walsh and systems analyst Arlo Glass.

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.

While the newly-upgraded CTU is challenged by some unexpected and complicated circumstances, Jack Bauer becomes even more involved in preventing an upcoming assassination attempt on Omar Hassan, a visiting President. Meanwhile, international security is jeopardized by an explosive event, and Jack is reunited with agent Renee Walker.

Four explosive hours after being unwillingly drawn back into action, Jack Bauer reteams with a risky Renee Walker to track some very dangerous leads. Meanwhile, back at CTU, a desperate Dana Walsh faces tense and untimely circumstances, and emotions escalate when President Taylor learns of a larger looming threat that jeopardizes the peace accord with President Hassan.

Undercover Agent Renee Walker confronts her painful past when attempting to broker a deal with a ruthless, but very well-connected German arms dealer. When CTU shifts its focus from the perilous circumstances surrounding Jack and Renee, lead analyst Dana Walsh comes up with a plan to quell her situation and Chloe O'Brian puts Arlo Glass in his place. As Jack and Renee’s undercover mission takes unexpected turns, the Hassan family turmoil has President Taylor reeling as the peace agreement is jeopardized.

Despite averting the assassination attempt on foreign peacekeeping leader Omar Hassan, Jack Bauer's day intensifies when he is forced to go further undercover to secure the unsecured enriched nuclear materials. As international delegates reconvene at the United Nations, President Taylor's goodwill comes into question and CTU races against time to assist with the mission.

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.

As Jack's day enters the early morning hours, the nation remains vulnerable, and President Taylor presses on with her international peace process. With the possibility of colossal failure facing CTU, attention turns to who is to blame, and things get personal when operatives take matters into their own hands.

As the terror threat continues, the Hassan family turmoil fans the flames of the increasingly urgent situation. When Jack closes in on a person of significant interest, a tense meeting between President Taylor and Omar Hassan takes an unexpected turn as the global security stakes are raised.

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.

While Jack and Cole team up in the field to shield New York from the calamitous threat, a hostage situation has CTU completely stressed out. Meanwhile, unrelenting parole officer Prady presses on in his investigation, and unexpected developments send the Hassan family into a major tailspin.

As the imminent terror threat nears and CTU copes with the day's explosive events, the onerous NSA intervenes. Conditions at CTU remain tenuous and field operatives find intense action when Jack Bauer leads them on a risky mission. Meanwhile, Chloe and Dana make game-changing moves.

President Taylor's vision of global peace has been foiled over the last 13 hellish hours, and the situation worsens when the imminent threat of mass destruction clarifies. As her idealistic nature becomes a point of contention, she tasks Jack Bauer with a crucial mission, and advisor Ethan Kanin returns in the heart-stopping.

President Taylor undergoes a game-changing setback; President Hassan makes a decision that shocks his loved ones; trusted confidantes become enemies of the state.

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.

With only seven hours left in the series' final harrowing day, Jack Bauer sets out to avenge the tragic life-changing events that he has endured. As things become even more personal for Jack, he heads to CTU for an intense meeting after learning of a devastating development. Meanwhile, on the verge of achieving peace on a scale that has eluded the world for generations, President Taylor becomes deeply conflicted when former President Logan sits down at the bargaining table.

With only six hours left, the clock races toward the series finale as President Allison Taylor faces impossible choices and much to the dismay of CTU, she enlists a private security firm to complete a sensitive task led by Mark Bledsoe. Meanwhile, Jack calls in a favor to his old friend Rick Vickers before he embarks upon a crucial mission of his own.

With only five hours left, the clock races toward the climactic series finale as Jack stops at absolutely nothing to avenge the emotional setback of losing his beloved partner Renee Walker. Meanwhile, the administration attempts to keep the historic and pivotal peace agreement on track as undermining forces surface.

With only four hours left, a rogue Jack Bauer stops at nothing to determine who is behind the day's most devastating events, and he uncovers an unexpected lead.

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.

Emotions run high as the harrowing day climaxes with resolute President Taylor closing in on a world-changing peace treaty and a vengeful Jack Bauer taking matters into his own hands for one last and unforgettable job.

Emotions run high as the harrowing day climaxes with resolute President Taylor closing in on a world-changing peace treaty and a vengeful Jack Bauer taking matters into his own hands for one last and unforgettable job.