Isla Fisher & Gal Gadot freaked out by Jon Hamm's driving

A fast-paced car chase scene in Isla Fisher and Gal Gadot's new movie was almost a real mess, because one was lactating and the other was trying not to be sick.

Gadot plays the cool, calm and collected spy wife of Jon Hamm in Keeping Up With the Joneses, but Isla, who was a new mom while filming the action comedy, reveals the new Wonder Woman was a bundle of nerves during the movie's car chase scene.

"It was a bit like a family holiday," the Australian actress told TV show The Talk. "I was lactating and crying and screaming because I was so scared because Jon was driving so fast, and Gal gets car sick and Zach (Galifianakis) gets claustrophobic and Jon Hamm is just the dad, like: 'Kids, shut up!'"

Gal admits she really had to concentrate to make sure she didn't throw up: "I was just breathing and trying to keep myself together," she explained.

The actresses may not have enjoyed the car chase scene, but they did like locking lips for an intimate clinch in the film.

"I just said to my husband, 'You can't come on set that day! A girl's gotta do what a girl's gotta do'." Fisher joked, while Gadot revealed she enjoyed the preparation for the scene, adding, "Practice makes for perfection."

Keeping Up With the Joneses is in cinemas now.