President Logan finds out about Martha being in the motorcade and calls her to convince her to leave the motorcade; she refuses and hangs up. Logan discusses what to do with Mike Novick, but ultimately decides to sacrifice his wife to save potentially thousands of American lives.
Audrey calls Jack to tell him that Omicron made the nerve gas for the military, but they can't produce a direct link to Henderson. Jack arrives at the Omicron building and Chloe at CTU helps him gets him past security. Jack walks into Henderson's office-- but Henderson knew someone was coming and tasers him. Jack wakes up with Henderson pointing his gun in his face, and tells Jack that he never believed he was dead. Jack tells him he is with CTU and tells him about the nerve gas-- Henderson returns Jack's gun and offers to help investigate.
Edgar intercepts SATCOM chatter indicating a threat against the motorcade, but an angry McGill refuses to consider the threat until the nerve gas is found. McGill makes a scene threatening to fire Audrey when Audrey tries to convince him the threat is real. Audrey goes to Curtis and asks to invoke Article 112, removal of a CTU chief due to mental incompetence. Curtis agrees only to consider it.
McGill finds out about Edgar, Audrey, and Chloe's plan to warn Secret Service behind his back of the motorcade threat. He brings security to arrest them, but Curtis stands up to him and invokes Article 112. The guards side with Curtis, and they lock McGill up. Curtis releases Buchanan and puts him in command of CTU again. Buchanan undoes all of McGill's mistakes, and calls the President. Logan is shocked when he hears that CTU knows of the threat on the motorcade, but successfully covers for his complicity.
The terrorists attack the motorcade despite advance warning. Aaron Pierce kills a few of the terrorists before LAPD reinforcements arrive. Martha, the Suvarovs, and Pierce survive the attack.
Jack and Henderson go to the sealed Omicron department involved in the project and Henderson goes through records showing that most of the scientists died in mysterious ways. Henderson maintains his innocence and that he was framed years ago-- until he locks Jack in the secure department and leaves. Jack finds a bomb in Henderson's package and scolds himself for falling for Henderson's story so easily-- Henderson, meanwhile, calls and assures someone that CTU does not yet have enough information, and remotely detonates the bomb. Jack survives.
Bierko calls the President and tells him that because the attack failed, America must pay. Logan objects, stating that he did not issue the command to CTU. However, Bierko ignores the statements, and commences with his plan to detonate the gas.