Christina Applegate has revealed that Justin Long gets naked in new romantic comedy Going The Distance.
Christina voices Brittany in Alvin And The Chipmunks: The Squeakquel, while Justin voices Alvin, but he is also reunited with on-again-off-again girlfriend Drew Barrymore in the new romcom, out next year, which also stars Christina.
She hinted: "I saw A LOT of Justin Long over the summer, I did - You'll see the movie and you'll know why I said that."
The 38-year-old actress also revealed the movie, about a couple in a long distance relationship, is "very dirty".
Christina said: "It's called Going The Distance and it's with Justin and Drew Barrymore and then a whole slew of really awesome people.
"It's very dirty. It's the polar opposite of Alvin And The Chipmunks. These people will not be able to go see that."
The Anchorman star and Amy Poehler, who voices Eleanor in the Chipmunks Squeakquel, also joked about their best and worst Christmas presents.
Christina revealed: "A set of encyclopaedias when I was 18. I'm sorry Marm, you'll never hear, encyclopaedias when I was 18."
Amy, keen to impress a British audience, joked in a cockney accent: "My best present was bangers and mash and my worst present was, um... um a tight pair of knickers."
:: Amy and Christina voice Chipettes Eleanor and Brittany in Alvin And The Chipmunks: The Squeakquel, in cinemas December 21.