Watson is seen mouthing Daniel Radcliffe and Rupert Grint's lines during a take from Sorcerer's Stone

By Jodi Guglielmi
March 07, 2017 10:04 AM

Emma Watson came to set prepared while filming Harry Potter — maybe a little too prepared.

The Beauty and the Beast actress, 26, stopped by Jimmy Kimmel Live! on Monday where she couldn’t help but cringe while watching an outtake clip from her early days on Harry Potter.

In the clip, Watson is seen mouthing Daniel Radcliffe and Rupert Grint‘s lines during a take from Sorcerer’s Stone.

“This is actually quite traumatic for me,” she said as she burrowed her face in her hands. “I would ruin takes.”

She said she would learn everyone’s lines in a scene and accidentally catch herself saying their lines under her breath.

“[Director] Chris [Columbus] would be like, ‘Cut! Emma, you’re doing it again,’ ” Watson recalled. “I couldn’t help myself. I was such a loser.”

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Watson said she was so was so obsessed with the Harry Potter growing up, that she inadvertently memorized nearly every line from the books.

“I really love those books,” she said. “I really wanted to do my job well and I kind of overdid it.”

Watch the hilarious clip above!