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.

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.

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.

As dawn breaks over New York, President Taylor endures a game-changing setback as the threat of mass destruction looms. Meanwhile, President Hassan makes a shocking decision that surprises his loved ones. But before long, trusted confidantes will become enemies of the state, and it's only the beginning of the betrayals that are to come as the race against time ticks over two pulse-pounding hours.