Jed weighs his options for responding to the bombing as Israeli and Palestinian forces face off against each other; Josh has an interesting reaction when Colin arrives at the hospital to visit Donna; Kate and Leo clash over the advice she's giving Jed; Josh assumes a diplomatic role when the Palestinians approach him to initiate settlement discussions; Toby and Charlie prepare a reluctant Jed for throwing out the first ball at Camden Yards; Donna's life is threatened when she develops a pulmonary embolism; Jed reflects on the days prior to his first inauguration.

Hoynes throws his hat in the presidential ring, and asks Josh to join his campaign; Jed's health begins to deteriorate; Toby and Kate head the protocol negotiations with the Chinese over the arrangements for the upcoming summit, which is jeopardized when Jed mistakenly accepts a Taiwanese flag at the National Prayer Breakfast; Bernard takes his new position as head of the Gifts Unit to heart as he gives Charlie a hard time about retrieving the flag so that it can be returned; Josh has his hands full with a pro-Taiwanese senator holding a hard line on recognizing their independence; Bob Russell crashes an Oval Office photo op with the governor of Pennsylvania, who's also another potential presidential candidate.

Valentine's Day starts badly when the Iranian air force shoots down a British airliner, killing 100 passengers. The U.K. Prime Minister threatens to retaliate by bombing nuclear reactor sites, which could doom future support for political reformers in Iran. But C.J. has made an agreement with Abbey to allow the President to get more rest, and she is reluctant to awaken him at 5 A.M. to deal with the crisis. Meanwhile, Toby and a visiting law professor answer questions from a foreign delegation that is trying to write a new constitution for the former Soviet Republic of Belarus, and harried staffers pass the buck of Leo's traditional meeting with the new Miss World.

Santos is working on campaign strategy, Ellie's getting married, Abbey is welcoming guests, Bartlet's making jokes, China and Kazahkstan are about to go to war, Carol makes an appearance, and Josh may get fired.

The Santos campaign meets up with Rock the Vote and lots of musicians are around for a star-studded episode. Helen gives a lecture to MANA (a National Latina Organization, formerly Mexican American National Association) but her heritage doesn't help her when trying to deliver part of the Santos campaign message. Toby is being pressured by the Attorney General, Blake, to reveal his source and it's affecting his relationship with his kids. He tries a little psychological warfare of his own to get Blake to back down. Toby is also giving Josh campaign advice which includes plans to increase courtship of the Latino vote. Elsewhere on the campaign trail, it's Halloween and Toby's kids and Santos' kids are dressing up for the occasion.