Kristen Stewart Hurt, 'American Ultra' Funny Violence: Fake Scars Frighten Cannes Flight WATCH

Kristen Stewart's highly-anticipated new film "American Ultra" finally hits theaters on Friday (August 21). How many fans are excited to see K-Stew portray a bada$$ stoner girlfriend alongside Jesse Eisenberg?

Apparently, playing the role of Phoebe pushed 25-year-old Stewart to her physical (and emotional) limits. But the "Twilight" sweetheart insists that everything was worth it in the end. Robert Pattinson's ex enjoyed her entire time on (and off) camera:

"This is hilarious," Stewart recently told CBS News. "This is something light. I can hang out with Jesse for a couple of months and do something."

Both Stewart and Eisenberg went through months of special training to learn how to fight with rather unconventional weapons including spoons and mascara tubes:

"It looks realistic," the "Still Alice" beauty explains. "It looks like these real people who are not action movie actors stuck in this situation."

Actual battle wounds did occur, but Stewart learned to go with the flow and simply enjoy the experience:

"[It] ended up being the hardest job, emotionally, physically, like hurt myself constantly. All the scenes are like level 10 dramatic, cause the characters are reacting but that's what makes it really funny."

Apparently Stewart likes the "bruised and battered" look, however. According to USA Today, she would sometimes wear such gory makeup after shooting to still "look tough."

"I would walk down the street after work and go get dinner (with the fake scars)," she joked at the LA movie premiere earlier this month.

But perhaps she took things to extremes during a "fancy" flight to Cannes. Some fellow passengers were so alarmed with her scary look, Stewart eventually went to the bathroom and removed the fake scars. Most people are relieved, saying things like "Oh honey, I thought that you had been very mangled." Still, she'll never get rid of such memory-filled souvenirs!

"I like them. I keep them."

Ha.

Watch K-Stew share the rather amusing story below:

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