Farewell party at 'The Office' after 9 years

"I was like, 'Yeah, we should give it a shot,'" said Merchant. "But the chances of it actually happening, and the chances of it succeeding if it does happen, are very, very, very, very slim."

And initially, it seemed he was right. An early plan for it to land on a cable network was a bust — at the time, BBC America was already running the original series.

But Kevin Reilly, then at NBC, would be its rescuer.

"I felt right from the start that even though the show was different — the pacing of it, the idea of a mockumentary, the narrative structure — that it was still rooted in an age-old half-hour convention, which is an office place," said Reilly, now entertainment head at Fox. "I knew it could succeed in broadcast ... eventually."

Of course, his instinct would have to contend with Jeff Zucker, then NBCUniversal's chief. Zucker hadn't been too keen on the show in its pilot stage or after its low-rated six-episode first season. The screening process for shows began for the next season's lineup — and spirited debate followed.

"Let's just say there were very senior members of the NBC brass at the time who were quite clear that this was not going to be picked up again," Reilly said.

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There was a frenzy of behind-the-scenes meetings with many senior executives, said Reilly. "It was an extraordinary time, because NBC was very structured at that point. Because I was a new guy and because NBC was in the process of its wheels coming off, it just became very political and very supercharged."

Daniels, the American adaptation's captain, wasn't exempt from the mess. He had to pitch Reilly on ways to boost ratings in the second season — part of the plan included making Michael Scott, played by Carell, a central character with a little more heart.

"I had a list of all these moments that I wanted to do," Daniels said. "Like, he should give someone really good advice, he should make a great sale — they all became episodes in Season 2. We wanted to show that the employees actually did like him. And the Jim and Pam drama really heated up."

The series made it onto the fall schedule in 2006 — just as Carell's movie career was picking up — and avoided hitting the shredder from then on.

"The Office" was one of the first shows available on iTunes and consistently one of the top performers on the site. Its early recognition of tapping into Web-savvy young consumers was one of its hallmarks.

Before its second season, stand-alone webisodes were made available on NBC's website. The ratings would pick up, and the series would go on to score an Emmy in its second season for outstanding comedy series.

Zucker, now onboard with the show, would even commission supersized episodes. At its height (its fourth season), the show touted a respectable 7 million viewers.

"I felt very strongly that as the network was going down, it needed to stand for something," Reilly said of his reason for lobbying for it. "To me, 'The Office' represented a new version of what NBC could stand for, which was quality and smart comedy."

Silverman, who would eventually go on to replace Reilly at NBC, had wanted to stretch it further — suggesting spinoffs from as early as Season 3, when another office branch was introduced. One proposed spinoff, which would have centered on Andy Bernard (Ed Helms), morphed into "Parks and Recreation." Another centered on Dwight (Rainn Wilson) would get dropped.

"It felt like there were so many things that were going to trip it up along the way," Merchant said. "So when it was finally on its third season, it was like, 'How did we get here?' And as it's about to wrap up in its ninth season — its ninth season! — it's like, 'No, really, how did we get here?'"

Walls come down

Part of the final season's conceit has been tearing down the fourth wall. At last, TV viewers get to see the documentary crew that has been skulking around Dunder Mifflin all these years. Their documentary is set to air.

Inside the cluttered Dunder Mifflin set — tucked away in Van Nuys, a mere 2,700 miles from Scranton — the office workers are reading the first reviews of the documentary of their workplace. Not surprisingly, in the scene, Phyllis Smith, who plays congenial Phyllis Lapin-Vance, is having computer problems and is unable to scroll through the website.