Paging Ms. Spears! Keira Knightley may be an Oscar nominee who has appeared in hit films like Pirates of the Caribbean and Pride & Prejudice, but as she revealed on The Graham Norton Show, she often gets mistaken for other A-List celebrities.
Natalie Portman is the most common one. In the 1999 film Star Wars Episode I: The Phantom Menace, Knightley, 29, played Oscar winner Portman's handmaiden and decoy, so she's used to those comparisons.
"Natalie Portman I get a lot, and I get chased through airports," Knightley revealed to host Norton on June 13. "I feel quite sorry for her because she must get chased a lot because it's happened like five times where someone's been like 'NATALIE, NATALIE, NATALIE.' And I'll sign and take a picture as Natalie."
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Portman isn't the only look-alike comparison that Knightley regularly receives, though.
"I get Kate Winslet as well," she continued. "But the one that's surprising is Britney Spears. I get quite excited because I quite like the idea that I could do like that [mimes shimmying], which I can't do. So I've been Britney Spears like three times."
"So you sign for her?" host Norton asked.
"Oh definitely sign, and have a picture. Absolutely," Knightley confirmed.
The show's other guest, Samuel L. Jackson, could relate to the Begin Again star's fan mix-ups. Back in February 2014 when he was promoting Captain America: The Winter Soldier, Jackson was mistaken for pal Laurence Fishburne by a Los Angeles reporter. It caused the Quentin Tarantino favorite to fly into a rage, calling out the journalist for his mistake.
"Everybody said I was irate and embarrassed him, but I got a lot of calls from a lot of people in Hollywood who really hate him and said, 'That was so great!'" Jackson told Norton, laughing. "I've been every famous black actor in the world."
Knightley went on to talk about her role as a singer-songwriter in the new film Begin Again where she plays the girlfriend of a rockstar played by Adam Levine. Norton saw parallels between her character's life and Knightley's real-life marriage to Klaxons rocker James Righton.
"He'll be very happy to hear himself be called a rockstar! Yes, I am! I'm married to a rockstar!" she said, laughing. "He tried to teach me how to play the guitar for this film, which nearly ended in divorce and murder. I've never been more angry. If you are married to someone, don't get the other one to teach you to play a musical instrument."
Though her husband does have a loyal fan base, Knightley doesn't get jealous of the cheering crowd.
"I do like watching him from the side of stage. Only with them it's more beefy dudes than girls," she quipped. "With bands, I think they should have knickers thrown at them, which they haven't. I've seen a bra thrown at them, which was quite big. Clearly he's not into that."