Steve Carell was 'Reluctant' to Return for the Series Finale of The Office, Says Jenna Fischer

Steve Carell's bittersweet cameo on The Office's 2013 finale almost didn't happen, as the actor was "reluctant" to reappear as Dunder Mifflin branch manager Michael Scott.

Carell played Scott for seven seasons before exiting the show in 2011, during its seventh season. But the actor reprised his role in the May 2013 season 9 series finale, where he appeared as the best man at Dwight Schrute (played by Rainn Wilson) and Angela Martin's wedding.

On the Oct. 30 episode of the Office Ladies podcast, Carell's co-stars Jenna Fischer  — who starred as Pam Beesly on the show — and Angela Kinsey — who played Martin — recounted how the actor's appearance in the finale came to be.

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"Well, it was [series creator Greg Daniels] idea to have Steve come back. He had wanted that for a very long time, and he asked him pretty early in season 9," Fischer, 50, explained in the podcast.

Fischer continued: "But Steve was reluctant. He felt like Michael's story had really ended. He didn't want to open it back up again, and he especially did not wanna come back after two years and have this finale episode be about him."

"Steve really felt like, 'My character had his ending.' This is everybody else's ending, and he didn't wanna overshadow that."

"Well, he's very gracious that way," Kinsey, 53, interjected of Carell.

Daniels who ultimately figured out a way to realistically include Michael Scott in the final episode — and got Carell to agree to be a part of it.

"Greg had the idea of the final episode being Dwight and Angela's wedding, and Steve agreed Michael would be there," Fischer said.

Added Kinsey: "I believe that. I believe Michael would wanna be there for Dwight and Angela."

"It was a creative reason that was supported by history, you know," Fischer concurred.

Carell uttered his character's famous line after surprising Dwight and taking over best man duties from Jim Halpert (John Krasinski). Dwight told Michael, "I can't believe you came," to which Michael replied emotionally, "That's what she said."

Carell's appearance on the final episode was a surprise for viewers at home, with his name not included in the show's opening credits.

On the podcast, Fischer noted that keeping Carell's appearance on the finale a secret was "really epic to pull off," with many of the cast members (including Kinsey) kept in the dark.

"It was really hard not to tell you ... and you did not find out until he showed up on set that day," Fischer told Kinsey, who added that she remembered the "exact moment" she realized Carell was there.

"The set PA turned to me and said, 'Steve is here.' ... I said, 'What?' And I opened the door, and there he was — he was sitting in hair and makeup," Kinsey said.

According to Fischer, Daniels did not even tell NBC — the network on which the show aired — that Carell would be in the episode.

"They had a scene at our table read ... but it was a placeholder," Fischer said, adding that Carell signed a secret contract that was kept under lock and key until the day he showed up on set.

A cut of the final episode — without Carell — was also filmed to further pull the wool over executives' eyes. Executives ultimately didn't see the actual final episode of the series until one day before it aired to the public.

"He was afraid that if he turned in any footage of Steve Carell on the show before it aired that NBC would make promos out of it and ruin the surprise," Fischer said of why Daniels kept it such a secret.

Krasinski previously spoke to PEOPLE about keeping Carell's last hurrah under wraps in an earlier interview.

"It was so thrilling. We all just flat-out lied," the actor told PEOPLE. "I lied to Letterman! I have to apologize to him for that at some point. It was just one of those things that we all vowed and had to protect. Look what happened — it was the best. The 'that's what she said' [throwback] was the perfect use of Steve."