Credit: Dave M. Benett/Getty Images

London called, and Jennifer Aniston answered.

The star, 41, rocked the red carpet in London on Thursday for the premiere of Bounty Hunter.

With costar Gerard Butler standing by, Aniston greeted fans and photographers in a sparkling Valentino minidress, Alexander McQueen tuxedo jacket, Fred Leighton jewels and super-sexy, strappy Jimmy Choo heels.

Although they've denied any romantic involvement, Aniston and Butler have become buddies.

"He's just fun," Aniston said last month of Butler, who helped her celebrate her 41st birthday in Cabo San Lucas, Mexico. "Gerry's the most unpretentious guy."

The feeling's mutual. Butler admitted to Men's Journal that they've become close -- and then regretted a raunchy joke he made.

"Over Christmas, she had a tree-trimming party that I went to. Yeah, I trimmed her bush," he joshed to the mag. "S***. Please don't put that in."

Tell Us: what do you think of Jen's red carpet look?