With Bartlet back in the Oval Office, and back in his wife's bad books, the hunt for a Vice President begins.

A North Korean pianist announces his intention to defect in the Oval Office. While the staff passionately debate his request they also fight to get the President's choice of Vice President nominated by a new and hostile Speaker of the House.

Multiple members of the team start questioning the direction of the White House, including one member entertaining job offers. Those who aren't are starting to stumble, including Josh and Amy.

Leo is left manning the fort when the President goes AWOL whilst visiting tornado victims. Josh is not in the position to lend a hand as he deals with the fallout from a gross miscalculation and lack of judgment.

Deputy counsel Joe Quincy is quietly enlisted by Toby to approach the ailing Chief Justice about possible retirement. With Josh still incapable of lobbying effectively, Leo brings in help to hammer out the budget, but success looks a long way off with a hostile Speaker making negotiations tricky.

President Bartlet refuses to let Speaker of the House Haffley hold him hostage on the budget and allows the government to be shut down.

A nuclear device is tested in the Indian Ocean, but none of the known nuclear powers will claim responsibility, leading to the possibility of a terrorist group holding missile tests. Vice President Russell, heretofore dismissed by west wing staff as a joke, a four-term congressman alleged to be securely in the pocket of a large Colorado mining company, recalls a junket he'd taken early in his political career in which a drunken Israeli statesman confessed to secret missile tests. Russell visits the sit. room and puts the military and national security leaders at ease, leading the president and Leo to reassess the man's political gravitas. Bartlet then drags the Israeli p.m. to the White House, where they debate the power of the U.S. to dictate which states should have nuclear capabilities.

A Republican Congresswoman targets Ellie in an attempt to discredit the President; C.J. urges Abby to appear on Sesame Street; Josh works to keep a judicial nominee from withdrawing.

The President finds himself at odds with Leo, and the entire country, on his position regarding retaliation for the bombing in Gaza.

Josh visits a car dealership and is seduced by both a hybrid and a monster SUV, despite knowing that Congress is unlikely to raise fuel efficiency standards. For political cover as well as genuine concern, he meets with representatives of the alternative energy industries. Charlie has graduated from college and is reluctant to keep his promise to the President of finding a "real" job. Following press complaints about Toby he agrees to take deportment lessons from Annabeth. C.J. visits Leo at his hotel and finds out why he's so insistent that the President play chess each week.

After spending months negotiating a difficult summit with China, Josh is dismayed to learn that the President accepted a flag symbolizing Taiwanese independence. Vice President Hoynes appears on television to promote his book and indicates a desire to return to politics. With the Iowa caucuses only a few months away, Vice President Russell and others begin positioning themselves to win the Democratic presidential nomination. President Bartlet finds tying his bow tie unexpectedly difficult.

Magicians Penn and Teller give a controversial performance at Zoey's birthday party in the White House that threatens to drown out the news of the impending China trip. President Bartlet goes to New Orleans on his way to China after unexpectedly requesting briefings be postponed until they are in the air. Josh tries to decide which Democratic presidential candidate he wants to support, and is alarmed that Bartlet wants to appoint California Republican Senator Arnold Vinick to be Ambassador to the United Nations.

President Bartet's attack of multiple sclerosis requires hasty reorganization of the summit in China. Unable to endure the long meetings, he becomes frustrated when the Chinese take advantage of his absence to drag their feet over North Korea. Back at the White House, Josh is told by NASA that a large asteroid is on a collision course with earth; staffers are unsure whether to prepare for the end of the world or not. Donna becomes frustrated when Josh continually postpones what she says is an important conversation. With the New Hampshire primary looming and Vinick looking like a formidable opponent, Josh and Leo try to find a Democratic presidential candidate they can believe in.

On the same day that an anti-gay-marriage amendment is attached to the federal budget, an Internet rumor surfaces that C.J. is a lesbian. Josh and Toby attempt to kill the amendment without forcing the President to publicly take a position on this unwinnable issue. Congressman Santos considers Josh's proposition that he run for President despite having told his wife that he's done with politics. Donna begins her new job while Josh struggles to cope with her difficult replacement. Abby and C.J. meet with the President's doctors to decide how to adapt his schedule to the increasingly debilitating effect of multiple sclerosis.

A day in the lives of presidential candidates Bob Russell, Matt Santos, and Arnold Vinick, who are in Iowa trying to gain support for their campaigns. Iowa is the first state in the nation to hold their presidential caucuses, and issues affecting farmers and rural areas are the focus. The most important issue on the table is the large federal subsidies for ethanol fuel given to corn growers, which is supported by Iowa residents but seen as naked pandering by the rest of the country. Josh continues to clash with Santos over winning votes instead of proposing radical policy. Donna and Josh continue to avoid speaking about the state of their relationship.

Five days before the New Hampshire Democratic primary, the Santos campaign risks extinction as Matt has not been invited to the last debate. Josh proposes a number of strategies to get Santos into the debate, including deal-making, legal challenges, attack ads, and publicity stunts - but the Congressman is reluctant to play along. With Josh scrambling to keep the campaign alive, Santos calls in help from Washington to tune his message. Hoynes and Russell launch attack ads on each other's records, and Josh realizes that a desperate long-shot is needed to keep Santos in the race.

Hoynes and Russell are campaigning in New York, confident of their prospects in the California primary. Santos needs to do unexpectedly well in California in order to stay financially afloat; another third place finish will see his donors shift their money elsewhere, finishing his campaign. Santos's message of education and health care is overshadowed when California passes a law prohibiting drivers licenses for illegal immigrants. Despite the bill being widely supported by most voters, Matt cannot publicly endorse it as he's counting on the support of Latino voters, who expect him to denounce it.

Rumors circulate in Washington yet again about the state of Fidel Castro's health. As C.J. begins to look into the issue she uncovers some dark secrets regarding the United States' relationship with Cuba which appear to involve Leo, the President, and Kate Harper. Despite how closely guarded and potentially explosive this information is, a startlingly large number of government agencies and officials appear to know bits and pieces of the story. This results in undercover political maneuvering to avoid what is expected to be an enormous political disaster. Meanwhile, Charlie calls in different professionals to deal with a suspected termite problem in the White House.

Senator Arnold Vinick easily wins the Republican nomination on the night of the New Jersey primary, but has difficulty picking a running mate. Choosing Reverend Don Butler would virtually guarantee him the presidency, but their differing views on abortion and religion would make it a political union rather than one based on shared ideology. The Democratic nomination is a toss-up between Santos and Russell; Hoynes is running a distant third. With no clear nominee going into the convention, the Democratic party risks appearing unsure about both Santos and Russell - a position that President Bartlet does not want the Republicans to be able to exploit.

While Vinick and the Republicans deliver a flawless albeit predictable convention, the Democratic convention looks to be more like a pie fight as there is no clear favorite. Russell tries to preempt the floor vote by hinting offers of the vice presidential nomination to both Santos and Governor Baker of Pennsylvania. Charlie and Zoey's relationship is becoming more serious, resulting in different reactions from the President and the First Lady. An air leak on the International Space Station will kill all three astronauts unless a rescue mission can be launched. NASA advises that their shuttles are unfit for flight, but then hints at another solution.

WHO WILL BE THE DEMOCRATIC PRESIDENTIAL CANDIDATE? - It's the Democratic National Convention and the race to become the Democratic Presidential candidate has narrowed to three candidates: Russell, Baker and Santos. Also, Bartlet must wrestle with the decision to launch the super-secret defense shuttle to rescue the astronauts trapped at the space station and risk national security or let them die.

President Bartlet and his current and former staffers come together for Leo's funeral.

A nuclear device is tested in the Indian Ocean, but none of the known nuclear powers will claim responsibility, leading to the possibility of a terrorist group holding missile tests. Vice President Russell, heretofore dismissed by west wing staff as a joke, a four-term congressman alleged to be securely in the pocket of a large Colorado mining company, recalls a junket he'd taken early in his political career in which a drunken Israeli statesman confessed to secret missile tests. Russell visits the sit. room and puts the military and national security leaders at ease, leading the president and Leo to reassess the man's political gravitas. Bartlet then drags the Israeli p.m. to the White House, where they debate the power of the U.S. to dictate which states should have nuclear capabilities.

A North Korean pianist announces his intention to defect in the Oval Office. While the staff passionately debate his request they also fight to get the President's choice of Vice President nominated by a new and hostile Speaker of the House.

With Bartlet back in the Oval Office, and back in his wife's bad books, the hunt for a Vice President begins.