Bryan Cranston says Jenna Fischer 'saved everyone's life' while they were filming the infamous bus episode of 'The Office'

• Bryan Cranston said Jenna Fischer saved the cast and crew of "The Office" while filming an episode he directed.
• They were filming on a bus attached to a trailer that was incorrectly hooked up to a cooling system and could've been poisoned by carbon monoxide.

Bryan Cranston told host Stephen Colbert on Monday's episode of "The Late Show With Stephen Colbert" that "The Office" star Jenna Fischer "saved everyone's life" while filming an episode that aired in 2012.

In the episode called "Work Bus," employees of the fictional Dunder Mifflin Paper Company, who are being followed in the mockumentary series, move onto a bus to work while fumigation is going on at the office.

The "Breaking Bad" star, who directed the episode, said that to bring the situation to life, the actors filmed in a trailer that was attached to "a refrigeration system, an AC system."

"They didn't think that where the intake for the refrigeration system was was exactly lined up to where the tailpipe of the bus was," Cranston told Colbert. "So, the exhaust of the bus was going right to the intake, cooling it."

He said that Fischer alerted him to the situation: "She said, 'I smell exhaust, it's coming inside the bus.'"

Cranston admitted that he didn't believe Fischer until he investigated the situation himself. "I got a chair and I stood up on the thing and I stuck my nose up in there and sure enough it was billowing down," he said. "It was carbon monoxide."

"I wasn't quite sure so I got a second wind. I got some more, I got nice and dizzy and then realized 'Oh my God, we could've all been dead,'" Cranston continued.

He joked that "it would've been one hell of an episode," though they would've all died.

Cranston also lightly pointed out that "it's not fair" that Fischer and former costar Angela Kinsey refer to the episode as "Death Bus" in their 2022 book "The Office BFFs" because "no one died."

"Work Bus" was the only episode of the series that Cranston directed.