The actress made her name in Hollywood playing aristocrat-turned-swashbuckler Elizabeth Swann in the hit Disney trilogy.
A fourth movie is in the works, with Johnny Depp already onboard to play Captain Jack Sparrow one more time. But Knightley is keen to move on from the role.
The actress tells Moviefone.com, "It was a completely fantastic experience, and it was an amazingly large portion of my life, but I don't think I need to go there again. I think that it's done. But I'm very excited to see the next one. And he (Depp) is so wonderful in that character. I think it'll be wonderful."
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