While on his way to a China Summit, President Bartlet has suffered an MS attack that leaves him significantly impaired. Unable to walk, they shorten the summit and Bartlet ends up frustrated at his inability to be in the room. On the last day of the summit, he manages to get a 1 on 1 meeting with the Chinese President to get the real goal of the summit done, North Korea nuclear talks.
Meanwhile, Josh struggles with the realization that there's no good Democrat running for the Presidency. Eventually he realizes that he has to pick his own candidate and he finds one - Matthew Santos, the Texas representative who decided to not run for another term in office. He flies to Texas to talk to Santos about it.
This episode contains examples of:
- Determinator: When Bartlet's MS leaves him paralyzed on the plane to China and the staff are talking about turning around he silences the room and, lying down, declares "This plane is going to China." Then he negotiates alone with the Chinese President for 2 hours when the doctors said he could only sit up for half an hour.
- Title Drop: Bartlet explains to Curtis what exactly the worst case scenario is for a large asteroid NASA is unsure will strike the Earth or not, specifically landing in the dense forests of Russia, causing a titanic fire that would rage unstoppable, throwing up ash and soot into the atmosphere and blocking out the sun. Thus, "impact winter."
- Wham Line: I quit. (Donna leaves the Bartlet Administration for an opportunity to advance in her career, which Josh isn't providing.)