Cheng calls Jack and tells him if he doesn't let him go, he will have Audrey killed. Jack goes after Cheng but sends Kate to rescue Audrey.

Kate saves Audrey from the sniper only to be surprised by a second shooter. Audrey is killed. Kate tells Jack who goes after Cheng with a vengeance.

Jack captures Cheng and gets both voice and face verification to the President who shows it to China and tells them to back down. They do. Then Jack realizes that Chloe has disappeared.

When Heller is told about Audrey he collapses. 

12 hours later, Kate Morgan turns in her badge and gun. Heller brings Audrey home in a casket, lamenting how due to his Alzheimer's he soon won't remember any of this, including her. Mark Boudreau is shipped back to the US to face charges of treason.

Realizing the Russians have Chloe, Jack makes an exchange. He turns himself over to the Russians to free her.