Farhad. CTU learns from the rescue of Hassan that terrorists have a plan to acquire nuclear rods from the Russian mob. With the help of Renee Walker, who is struggling to keep her life together, Jack goes undercover and forces the cooperation of Sergei Bazhaev's mob family. The nuclear rods are given to Samir Mehran, when Bazhaev's older son Josef betrays him for killing his younger brother Oleg who was exposed to the rods and was suffering from radiation poisoning who plans to make a dirty bomb on American soil. Hassan's head of security, Tarin Faroush is revealed to be a part of Mehran's group and they present an ultimatum to Taylor's government — she must hand over Hassan for execution or the bomb will be detonated. When Taylor orders that Hassan still be protected at all costs, a US black-ops team attempts to kidnap him. Jack Bauer and the rest of Hassan's protective detail kill all but one member of the team but upon learning of the ultimatum, Hassan turns himself into Mehran. With the nuclear crisis averted, CTU agents attempt to save Hassan and close in on Mehran. However, they arrive to see that Hassan has already been assassinated. Taylor is able to resurrect the treaty by convincing Hassan's wife Dalia to assume her husband's position as interim President and to sign the treaty on her country's behalf. Considering their duties to be over, Jack and Renee return to his apartment where they have a romantic encounter. However, a Russian assassin follows them there and fires through the windows to tie up loose ends. Renee is hit and a frantic race ensues as Jack rushes her to the hospital. She dies on arrival whereupon Jack vows to avenge her death and bring everyone involved in the conspiracy and cover-up to justice. He learns that the Russian government are behind everything as they see the treaty as a threat to their influence in the world and supported and funded Mehran's group to destroy the peace process. Allison Taylor though outraged by the conspiracy, still believes that good can come from the signing and decides to continue with the proceedings. She fears that Jack's actions will be enough to have the treaty called off and orders his lockdown. Jack frees himself and at the cost of a third world war, begins to hunt down and kill every member of the