Spoilers for this episode.
A nuclear cloud rises over Valencia as CTU confirms that four more weapons remain missing. Jack helps rescue a survivor from a helicopter dangling on a rooftop, then calls Buchanan to return to the investigation. Fayed has escaped with the remaining bombs, but the explosion destroyed his engineer and trigger device. He hires Darren McCarthy to find someone who can make the other warheads operational, offering more money to keep the search moving.
Assad tells CTU about a past weapons contact with Russian general Dmitri Gredenko. A search of Gredenko's business associates produces Phillip Bauer, Jack's estranged father and the head of BXJ Technologies. Jack asks to question him personally. Phillip has disappeared, and his household directs Jack toward his brother Graem. Privately, Graem complains that they should have killed Jack instead of handing him to the Chinese. When Jack calls, Graem acts pleased and claims he cannot locate their father.
At the detention facility, the FBI wires Walid and sends him back among the inmates to gather information, despite Sandra's objections. Palmer prepares a televised address while resisting demands for indiscriminate retaliation. Jack obtains Graem's address from Chloe and arrives unannounced. Graem evades questions about Phillip, so Jack knocks him out, ties him to a chair and presses for answers. When his brother still denies knowing anything, Jack begins suffocating him with a plastic bag.