Rob Lowe, The West Wing
President Bartlet may not have been eligible for another term, but Rob Lowe has elected to revisit NBC's The West Wing (Sundays at 8 pm/ET). "One line, and Rob was back where he left off," executive producer Lawrence O'Donnell Jr. says of Lowe, who's reprising the role that resurrected his career when The West Wing premiered in 1999.

Lowe left the show in 2002 in a dispute over salary and screen time. Now, with the series coming to an end next month, Lowe has signed on to make two guest appearances, with the first of his episodes airing on April 23.

"It was a great moment," says O'Donnell. "I saw him in the monitor, and he turned toward the camera and I realized that the series would have been incomplete without that moment. Seeing Rob and Brad Whitford together was like the good old days." Adds executive producer John Wells, "You thought it was going to be odd, but it wasn't. It was emotional for Rob, and it gave all of us closure."

SPOILER ALERT: Lowe's return as former White House staffer Sam Seaborn comes after the election that replaced the Bartlet administration with President Matt Santos and his crew. Former Bartlet chief of staff Josh Lyman (Whitford), who works for the new regime, flies to L.A. to convince his old buddy Sam to come aboard.

"Sam doesn't want to do it," says Wells. "He's gotten on with his life. He's working for a law firm and is engaged to be married." But Josh persists, offering Sam the opportunity to become deputy chief of staff. "In other words," Wells says, "Josh wants Sam to become his Josh."

But Josh doesn't make such an enviable role model. "We see Josh as we have never seen him before," says O'Donnell. "He's out of control, he's enraged. It becomes clear that he cannot run the White House without Sam. Sam is the only person who knows how to manage Josh."

Sam also has some personal advice for Josh, who is having relationship troubles with Donna. "Josh has to make a decision about their relationship," says Janel Moloney, who plays Donna. "Sam influences him and tells him: 'You are not just your job.'"

But what about Sam's potential new job? Will he, or won't he? Josh will get the answer when Lowe makes his final visit to The West Wing for the May 14 finale. If our vote counts, he'll say yes.