'The Office' cast members say they almost died twice while filming chaotic scenes for an episode

• Jenna Fischer and Angela Kinsey revealed the cast of "The Office" had two near-death experiences while filming an episode. 
• In "Work Bus," chaotic stunt driving caused the cast — and all of their props — to fall on top of each other. 
• Then, a portable air conditioning unit pumped exhaust fumes into the bus instead of clean air. 

Two cast members of "The Office" say they almost died twice while filming the "Work Bus" episode — a season nine episode set almost entirely on a bus.

In their new book, "The Office BFFs: Tales of The Office from Two Best Friends Who Were There," Jenna Fischer, who played Pam on the show, and Angela Kinsey, who played Angela, revealed that the episode quickly became dangerous during filming, Mashable reported, citing excerpts from the book. 

In the episode, which was directed by "Breaking Bad" star Bryan Cranston, Jim (John Krasinski) convinces Dwight (Rainn Wilson) that the office is too dangerous to work in and they must vacate for a few days. Instead of granting employees a few days off, Dwight rents a bus converted into an office.

Fischer wrote in "The Office BFFs" that 14 actors, four crew members, several desks, chairs, lamps, printers, a water cooler, a microwave, a giant-screen TV, and a coffeemaker were all in the bus for filming, Mashable reported.

"It was a very hot day and whenever we started filming, the air-conditioning on the bus had to be turned off because it was too noisy," Kinsey wrote, according to Mashable. "We were basically in a moving hot tin can with no air. I thought Brian [Baumgartner] and Creed [Bratton] were going to melt. Oscar [Nunez] looked dead inside."

In one scene of the episode, Dwight drives the bus to take the Dunder Mifflin employees to Laverne's Pies for some dessert.

The cast was meant to mimic falling into the sides of the bus as Dwight drove "like a maniac," but when the scene didn't look authentic enough, a stunt driver joined the cast on the bus to take them for a real ride, Mashable reported. 

"The stunt driver swerved HARD. I mean he cranked that wheel like Cole Trickle in 'Days of Thunder,'" Mashable reported Kinsey writing in book. "As a result, the entire cast and contents of the bus went flying into the side of the party bus! What no one had considered when they told this stunt driver to swerve as hard as he could without flipping the bus over was that none of our office furniture, props, or set decorations were securely tied down."

Kinsey added, according to Mashable: "We were all smushed up against the side of the bus. Ellie [Kemper]'s chair crashed into Jake [Lacy]'s. Jake's crashed into mine, and I was shoved against the glass window. Papers were everywhere. I caught our desk lamp as it slid into my lap. A few people fell on the bus floor, and we could barely see them because so many things had fallen on top of them."

Later in the shoot, the crew installed a portable air conditioning unit to keep the cast cool — but did so by pulling it behind the bus and threading a hose through the bus' sunroof , Mashable reported. 

As they resumed filming, Fischer noticed that the bus smelled funny, Mashable reported.

"The portable air-conditioning unit's INTAKE hose was right next to the EXHAUST pipe on the bus," Fischer wrote. "So that hose was sucking in exhaust and blowing it straight into the sunroof of the bus. We were all being slowly poisoned. Or not so slowly, actually."

Mashable reported that the pair refer to the episode as "Death Bus" because of how chaotic and dangerous filming became. 

The pair aren't the first cast members to reminisce about "Work Bus" — Ellie Kemper told Insider in 2019 that she laughed so hard she wet herself while filming the episode.