So, I'll admit, I was pretty worried about The Office there for a while. And it wasn't just the shakiness of the much-discussed hour-long format—though that's part of it, and I'll get to it in a minute. No, The Office has recently done something far more dangerous than simply tinker with episode length. It became, albeit briefly, a smug and joyless mockery of everything it used to be.

NBC's version of The Office always had a softer edge than the U.K. original, namely the degree to which the annoying boss —~Ricky Gervais' David Brent vs. Steve Carell's Michael Scott —~is tolerated by his employees. The vibe has always been one of "Nobody picks on my kid brother but me." So, while Jim and Pam and the rest live in constant shock of just how dumb and crass Michael can be, they're always willing to step up and defend him (if only slightly) when the aggressor is someone from outside The Office, or when they think he's had a little too much anguish for one man to bear.

See, for example, Season 2's "E-mail Surveillance," in which Jim had a party and invited everyone but Michael, who of course found out about it and crashed. It was awkward and pathetic, but even as Michael dug his hole deeper by attempting to sing a godawful karaoke version of "Islands in the Stream," Jim shrugged and joined him for the duet. He wasn't doing it out of kindness, exactly; it was more like he was tired of seeing Michael suffer for the day and decided to give him a reprieve. More accurately: For one moment, Jim realized Michael is just another lonely human being like everybody else, and treated him like one.

But this season, the show's fourth, marked some growing pains for the characters, and it was clear that no one quite knew what to make of the fact that so much had changed at once: Jim and Pam were together; Ryan had been promoted to corporate; etc. The greatest evidence for this was the way Pam went from modest to sarcastic and Jim went from sarcastic to screaming asshole in the first few episodes of the season, particularly "Fun Run," in which the couple spent the entire time not merely skewering Michael but coming up with new ways to hate him. Before they'd merely been smirky and aloof, but for a few moments they descended into genuine cruelty.

This is where the hour-long format deserves some of the blame. What speeds along as a tight half-hour of comedy flounders a little when forced to fill twice the length with the same amount of plot. "Fun Run" hit a wall in the interminable meeting scenes where Michael attempted to explore the employees' religious affiliations in an effort to exorcise The Office of a supposed curse of bad luck. The episode would have been tighter had the story focused on Michael hitting Meredith with his car and the subsequent 5K to raise money for her newly discovered rabies.

That's the real problem of the longer episodes: In being overlong, they lose control of the characters and erase some of the scruffy goodwill they've built up over the past three seasons. They're not just boring; they're antithetical to what the show is and can and should be.

This is why last week's "Local Ad" was such a good episode. In returning to its original, shorter format, the episode restored a control over the story lines and a quickly paced rhythm that had often gone missing from the bloated epics of the past few weeks—and in doing so, it also restored the characters to their truer selves. Jim and Pam were still bemused by the insanity surrounding them, but not angry about it; tolerant of Michael, not toying with him as they had been. What's more, Jim once again acted as catalyst for the episode's most genuine moment, when the employees all watched the cheesy commercial Michael had made and felt a rush of innocent pride at the dumb but harmless ad they'd helped produce. Everything was back: The mundane torture of office work, the ways to make time pass, but most of all, an ability to empathize with your antagonist. Short, yes, and sweet.

The Office

airs at 9 pm Thursdays on NBC.