Kristen Bell’s says the animators behind Disney’s “Frozen” may be the film’s “unsung heroes,” but it’s not all work and no play as they often troll the actors.

On “The Tonight Show Starring Jimmy Fallon” on Tuesday night, Bell said the hundreds of animators that worked on the movie sometimes threw in visual or audio tricks during screenings.

“They’re so good … But they also have a lot of fun together. So when they show us the pre-vis, like the pre visual, when I have to re-record a scene or slide a line in or something, what they show us often has tricks in it.”

Bell explained during the visual production process their characters are often nude and bald, which makes the initial viewing process already amusing, without the animators throwing another curveball at them.

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Foto: Kristen Bell's "Frozen" character, Anna, with Idina Menzel's, Elsa.sourceDisney

"I remember one time when I was trying to slide one line into this intimate scene where Elsa and I are sitting on the bed," she recalled.

Bell said after delivering Anna's line: "It's okay, you'll always have me," the animators added a fart noise.

"Yes they put in toots, there's been times where I've been like jumping from cliff to cliff and I don't make it," Kristen added.

Kristen Bell

Foto: Kristen Bell said other "tricks" the Disney animators got up to included showing her "Frozen" character, Anna, fall off cliffs.sourceThe Tonight Show with Jimmy Fallon/YouTube

Frozen 2 will be released in theaters December 22nd.

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