03/30/2010 05:12 am ET Updated May 25, 2011

'When In Rome' Premieres, Kristen & Kristin Show Off Backs

It was Kristen vs. Kristin at the "When in Rome" premiere Wednesday night in Los Angeles. Kristen Bell stars in the movie with Josh Duhamel, but "The Hills" personality Kristin Cavallari showed up in a hot pink minidress and may have stolen her back-skin thunder.

Also there was Fergie, married to the movie's leading man Josh Duhamel. Scroll down through the photos and decided.

(Kristen Bell)