The Russian and US Presidents are set to sign an anti-terror treaty when assassinations rock Los Angeles, a call from a distressed Chloe forces Jack into action and President Logan's wife believes there may be a conspiracy.

Jack and Chloe infiltrate Wayne Palmer's penthouse where David Palmer was assassinated, in the hopes of finding a clue to his murder. Jack convinces Wayne to cooperate and finds some information in Palmer's memoirs that leads him to the airport where the Russian president is about to land. CTU and Secret Service attempt to capture Jack, but they only find Chloe as Jack and Derek slip through their grasp. Martha tries to convince her husband that she received an important phone call from Palmer the night before his death, but a tape of their conversation seems to contradict her claims. Jack goes to the airport to find a lead, but a group of renegade Russian terrorists take hostages, including Derek, before he can act.

Jack conceals himself inside the airport hanger and surveys the Russian separatists, feeding information to Curtis and his assault team.

The terrorists begin executing hostages in an attempt to make Logan cave into their demands.

Martha discovers that all traces of her conversation with Palmer may not have been erased.

Jack is captured by the terrorists, who use Derek as leverage to force him to compromise CTU's assault operation. Logan refuses to give into the terrorist demands as the time of the co-signing of the treaty draws near. Martha tries to tell her husband of the evidence she uncovered about her phone call with Palmer, but Walt interferes with her efforts. A new representative from District arrives at CTU and begins to undermine Buchanan's authority.

Jack returns to CTU and has an emotional reunion with Audrey, while Curtis tracks the Russians and the stolen nerve gas.

Walt sends in a hit man to silence Jack.

Chloe discovers that Spencer has his own agenda at CTU.

Walt convinces Logan to have Martha institutionalized when she tells them of the attack on her.

Jack contacts Mike and asks for a secret meeting in hopes of gathering evidence against Walt.

Martha begs Aaron for help, while a desperate Walt tries to force Logan to aid him in his complicity with the terrorists.

Buchanan butts heads with Lynn over a decision to violate the president's orders, while the Russians attempt to escape with the nerve gas.

Jack poses as Rossler and manages to trace one of the canisters of nerve gas, but he goes against orders from the president when the terrorists target a shopping mall.

Logan and Martha quarrel when she learns of her husband's intention to cover up the real reason for Walt's suicide.

Jack takes Henderson to CTU for questioning. Once there, he faces an unhappy reunion with his daughter, Kim.

Mike appeals to Martha for help as Logan faces pressure from his Vice-President to declare martial law on L.A.

Lynn connects the theft of his keycard to an impending strike on CTU, but his warning comes too late to stop a terrorist from infiltrating the building.

Jack and Wayne locate a source inside Logan's administration who has information on Palmer's assassination. But things get complicated when they learn that Henderson is using leverage to keep her silent.

Audrey is forced to choose between Chloe and Buchanan as Homeland Security begins to absorb CTU.

Jack and Wayne locate a recording that definitively proves Logan's involvement in the terrorist conspiracy, but Henderson corners them in the hopes of destroying the incriminating tape.

Logan tries to cover his tracks by issuing a warrant for Jack's arrest.

Audrey contacts her father for help, while Chloe gives her cover while helping Jack evade CTU.