When you're megastar Emma Watson, life often imitates art. She loves books, she's an outspoken champion for equality, and even as a 9 year-old taking on her first acting role ever, she not only learned her lines, but everyone else's.

While promoting her current role as Belle in Disney's live action "Beauty and the Beast" on Jimmy Kimmel, some old footage came back to embarrass Watson -- and delight everybody else.

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Kimmel's staff unearthed an outtake from the first "Harry Potter" film showing a scene between little Emma, Danielle Radcliffe and Rupert Grint. The young actors are all delivering their lines deftly, the only issue is Watson is also visibly mouthing the lines of her co- stars.

"You laugh! This is actually quite traumatic for me, because I created issues because of this," Watson told Kimmel and his studio audience. "I would ruin takes. [Director] Chris [Columbus] would be like, 'Cut. Emma, you're doing it again. You're mouthing Dan's lines,' and I'd be like, 'I'm so sorry, so sorry. Oh, I feel so bad.'"

Watson went on to be endearingly self-deprecating about the incident. "But I couldn't help myself! I was... I was such a loser. I really loved those books. I really wanted to do my job well -- and I kinda overdid it."

Directed by Bill Condon, “Beauty and the Beast” stars Emma Watson as Belle, Dan Stevens as the Beast, Luke Evans as Gaston, Kevin Kline as Mauricer, Josh Gad as Lefou, Ewan McGregor as Lumiere, Stanley Tucci as Maestro Cadenza, Gugu Mbatha-Raw as Plumette, Audra McDonald as Madame Garderobe, Ian McKellen as Cogsworth, and Emma Thompson as Mrs. Potts. The film is set to open on March 17.

Via MTV