上一季中毒的jack已经复原，退休与外孙女一起，taylor总统和哈桑总统商讨签订去核协议，jack答应kim搬去洛杉矶，线人victor找到jack表示有针对哈桑的袭击，jack联系重组后的CTU，主管hasting派cole（此人是外勤指挥不是chole）去接应，jack带着victor干掉俄国人farmer的两个手下，但farmer用火箭轰掉了直升机，victor临死前告诉jack哈桑身边有内奸，女记者reed通过和哈桑的关系进入发布会现场。

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.

哈桑没被炸死换车离开，cole追踪farmer，farhad杀死保安逃走，farmer抓住cole但被赶来的jack击毙。Hasting承认低估了chole，dana通过farmer的纹身发现其属于俄罗斯某组织，并打算找唯一在组织中卧过底的探员renee前来协助。CTU在farmer尸体上发现了核原料。Renee答应hasting重新回到组织卧底，jack与renee重逢，他担心renee，要求与其一同行动。Farhad与卖家接触，jack与renee找到了中间人，renee为了摘掉监视手环锯掉了中间人的手。

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.

因为知道纽约可能发生核爆炸，哈桑急着寻找逃走的女儿，jack派人去接macos的妈妈，一wade的假释官布拉迪打电话给dana要找wade，jack劝降成功，macos指出tarin是共谋，哈桑妻子联系上女儿，女儿告诉了他们的位置。

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.

哈桑打伤jack自愿交出自己，jack告知taylor国防部长背着她劫持哈桑，恐怖分子得到了哈桑，留下了核弹，taylor逮捕了参谋与国防部长。Chole追踪到了恐怖分子劫持哈桑的车，dana暗中报信，恐怖分子改变路线，哈桑被中途交接带走，jack意识到CTU有内奸。

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

将军手下受伤没死，但一个医护人员悄悄毒死了他，然后联系了俄国代表！哈桑妻子愿意接替丈夫的事业继续签订和平协议，白宫高层致电chloe希望她能代替hasting指挥临时CTU，jack和renee滚床单，医护人员是杀手假扮，为了防止被认出来决定杀死renee，俄国代表对和谈的进行失去了兴趣，参谋建议taylor寻求罗根（前总统）的帮助，罗根出场表示有筹码与俄方代表谈判，chole就职后发现恐怖分子是被毒死的，并告知了renee，renee回想起了杀手的一些线索，但被杀手射死。

罗根找到俄罗斯代表，表示核威胁、政变都是俄国为了杀死哈桑组织会谈布的局，最终成功将俄罗斯劝回谈判，借此希望能重新在公众场合活跃，jack找到核卖家，卖家表示一切都是俄国政府的阴谋，dana策划了背后一切，jack回到CTU审问dana，罗根告诉taylor真相希望她组织jack，taylor来到CTU拒绝特赦dana，并打算带走jack，jack劫持了直升机逃走。

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.

罗根让taylor禁止杂志社刊登证据，jack安置好reed后捉住了罗根，罗根供出了俄罗斯代表团团长，chole释放cole让其去找出jack的同伴，reed打电话告诉了哈桑女儿真相，随后被逮捕，jack随后又杀死了团长，通过悄悄装在罗根身上的窃听器了解到下个目标是来签协议的俄国总统。

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.