Fashion Faceoff

Alexa Chung and Jena Malone wear the same Valentino gown (with slightly different undergarments). Plus, two denim showdowns and more star matchups that need your vote

LEA VS. CASSIE

What do you need to pull of this daring velvet Cushnie et Ochs dress (aside from an ah-maz-ing bod)? A whole lot of attitude, which both stars clearly have in spades, judging from those sexy "I-know-I-look-good" gazes.