Credit: Chris Haston/NBC

The final season of Chuck finally got underway last Friday (to decent ratings, considering), but as fans prepare for episode 2, executive producer Chris Fedak was talking up a Sarah-centric episode in the second half of the season that he promises will leave fans of Sarah Walker very satisfied.

“I have to say, for those fans who love Sarah Walker, it will be your favorite episode ever,” Fedak said of episode 8 today in a conference call with reporters. “It is an amazing, epic story that reveals a lot of secrets about Sarah that you could have ever imagined.”

After several seasons of waiting, the episode will introduce fans to Sarah’s “warm and caring” mother (Cheryl Ladd) and introduce them to Sarah’s original handler, which will be played by White Collar‘s Tim DeKay. “It’s not our funniest story, but we’re going into epic-land as far as Sarah’s past,” Fedak said. “It will be a jaw-dropping episode.”

While much of the rest of the talk was center on talk of the show’s final season, Fedak admitted that should NBC reverse their decision (long shot) and order more episodes, he’d find it hard to reject the offer. “If someone offered me the chance to write more Chuck stories, I would always say yes,” he says. “What we’ve done in the past is shut down the show and reconvene in the writer’s room and start over again. We’d have to do that in a much bigger way. It’s something we’ve done in the past and been able to figure out how to do…We’d build out a season 5.2”

The idea of more episode, he admits, is “exciting,” but the focus is currently on making episode 13 the ending. “I don’t think about that bridge until I’m half way across it and both sides are burning down,” he jokes.

Other teases:

–In episode 4, Chuck and Sarah go undercover at a Buy More convention, and it’s one of Fedak’s favorites. “I love it. It’s a very sweet, very different type of [episode],” he says.

–Episode 5, which is titled “Chuck vs. the Hack Off” and was directed by Zach Levi, is a play off the movie Swordfish and “one of the nerdier episodes we’ve ever done,” Fedak says. “We’ve got some amazing hacking sequences…It’s a really, really fun episode and we really get back into who Chuck was [before becoming a spy].” Bonus scoop: Lester finds himself in prison in the ep!

–Episode 7, which is the show’s Christmas themed episode, will air after Christmas. “It’s an incredible, high-intensity episode,” he says.

–While the series finale has several moving parts, Fedak says, “The Chuck and Sarah story will be the one you’re talking about.”

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