It's a busy weekend in TV land with an unusually full Friday night of new programming. Tonight marks the season premiere of "Spartacus: Vengeance" (10 p.m., Starz), reviewed this past Sunday in TV Week; the series finale of "Chuck" (8 p.m., NBC) and PBS's "Great Performances" debut of "Tony Bennett: Duets II" (9 p.m., WQED-TV).

Add in Sunday's premiere of HBO's "Luck" (9 p.m.), opposite a new episode of CBS's finally-free-of-football-delays "The Good Wife," and your DVR may start emitting steam from working overtime.

NBC's "Chuck" had one of the most topsy-turvy runs in TV history. Perpetually low-rated, the show, about a nerdy electronics salesman (Zachary Levi) who becomes a government secret agent, always seemed to be on the cusp of cancellation.

"The benefit of being on the bubble was that we told a lot of story," said executive producer Chris Fedak in a teleconference with reporters this week. "We never held anything. We always were ready to throw the kitchen sink into the story because we didn't know if we were going to be coming back for another season."

Assorted efforts by fans and advocates managed to stave off cancellation with a variety of campaigns (most famously, one involving Subway sandwiches), but producers often wrote their season finales unsure whether they also would be series finales.

"Well, hopefully I've gotten good at it," Mr. Fedak joked.

This time, producers knew going in that the show's fifth season would be its last. Mr. Fedak said producers devised the show's final moment a year ago as part of their pitch to NBC executives for one last season.

"[Past season finales] we wrote in such a way that they implied a big new season coming next year or in a few weeks," Mr. Fedak said. "And this time we knew that this was going to be our final episode. ... When we started working on the finale, it was much more like this will be the final chapter. This will be the final moment of this show, and we need to resolve these stories that we've been working on for five seasons now."