Kristen Bell and Cam Gigandet:Christina Aguilera become Sandwich!

Kristen Bell, Christina Aguilera and Cam Gigandet took the stage at the festival-anticipated film from Screen Gems, burlesque, in the summer of Sony, on Saturday.

Christina and Eminem will be the star guest of the final season of HBO's Entourage seventh Shes done [on-screen agent] Ari a favor and play for him, a source tells EW

FYI: Kristen and Christina are both wearing Herve Leger !