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.