Amanda Seyfried Saved a Crew Member on ‘Dear John’ from Drinking Channing Tatum’s Pee

Channing Tatum is quite the prankster.

Amanda Seyfried said she could keep up with her Dear John costar, with the two engaged in a prank war on the set of the 2010 film.

“He and I effed with each other the entire movie in a super, super fun way. He’s very, very funny, and we had a great time,” she told Deadline, recalling one particular instance where the prank almost got out of hand.

“He peed on my leg once, without me knowing. He peed on my leg on the beach, and I didn’t realize at first, and then I was like, ‘Oh, that’s why he’s standing so close to me,’ ” she shared.

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“There was a coffee cup very close by, and a little bit got in the coffee cup, and he ran away as I was screaming. One of the makeup artists picked it up and was about to drink it, and I saved her.”

Based on Nicholas Sparks’ best-selling novel of the same name, Dear John tells the story of a young soldier, John Tyree (Tatum), who falls in love with college student Savannah Curtis (Seyfried), while home on leave.

Seyfried once told E! News that Tatum was her “favorite co-star thus far,” because of their shared sense of humor.

“Channing and I have a very similar set behavior,” she told the outlet in June 2015.

“We don’t take anything too seriously, but we’re shooting a movie that’s very heavy, all about love and romance. It’s a tear-jerker, so we just like to play around.”