'The Office' star Jenna Fischer reveals that Jim's gas-station proposal to Pam cost $250,000 to shoot and was the 'single-most expensive scene' of the whole show

• Jenna Fischer revealed it cost $250,000 to film Jim and Pam's proposal scene.
• She called it the "single-most expensive scene" of the entire NBC series.
• Production recreated an East Coast rest stop in a parking lot in Los Angeles, California, for it.

"The Office" star Jenna Fischer revealed that Jim's proposal to her character, Pam, was the "single-most expensive scene ever shot" of the NBC sitcom. It cost the series $250,000 in production and post-production costs, she said.

Jim (played by John Krasinski) and Pam start out as co-workers at Dunder Mifflin before they become a couple.

In season five, Jim asks Pam, who was away doing a design course in New York City, to meet him for lunch at a gas station where he then proposes to her.

Fischer shared on Wednesday's episode of the "Office Ladies" podcast (which she cohosts with former "Office" costar Angela Kinsey) that the gas station where the iconic proposal takes place was based on a Connecticut rest stop that "The Office" series creator Greg Daniels visited as a kid.

"We did not actually fly to this location. This is the insane part," Fischer said, revealing that the sitcom's production team recreated the East Coast rest stop in a massive parking lot in Los Angeles, California.

The "Splitting Up Together" actress said on the podcast that it took the production crew nine days to build the set for the proposal.

Fischer said it was 'so bonkers' filming the proposal

Even though it lasted less than a minute in the episode, the show shot the gas station proposal with meticulous attention to detail - which is possibly why the scene cost a quarter of a million dollars to produce.

"[The production crew] used Google Street View to capture images of a real gas station," Fischer told Kinsey, adding that the crew consulted with these photos to create the set.

"To create the illusion of highway traffic, they built a four-lane circular race track around the gas station set," Fischer continued. "They set up cameras on the other side of this raceway and they had cars drive around it at 55 miles/hour."

Fischer clarified on the podcast that the cars driving around her and Krasinski when they were shooting the proposal weren't regular cars, but huge semi-trucks, adding that "you could feel the wind of these cars speeding past you."

"It was so, so bonkers," Fischer told Kinsey about her experience filming the scene, which also used "giant rain machines."

According to Fischer, after they had wrapped filming the scene, the creators also hired a special-effects company "to paint out the background" of the Los Angeles set to add "East Coast-looking trees."

The proposal takes place in a gas station because, Fischer said, Daniels wanted to have Jim's proposal be "in a very ordinary location."

However, Kinsey made the story about the proposal slightly less romantic by revealing that the parking lot they filmed at was actually a toxic waste site.

"An old ceramics plant or something had buried lead paint waste into the ground so they had to seal it and cover it," Kinsey told Fischer.

Kinsey's story didn't seem to particularly bother Fischer, especially since Jim and Pam go on to have a happy ending on the show.

In the series finale, the two have been married for several years, have two children together, and are planning to move to Austin, Texas.

"It was actually, to be there, really romantic," Fischer said, reflecting on filming the gas station proposal.