Jennifer Lopez Bares her Back in Sin City: PHOTOS

jennifer lopez rocking heavy eyelashes

Jennifer Lopez hit the red carpet last night at Planet Hollywood in Las Vegas for the premiere of her new movie 'Parker.'

The singer-actress was rocking a KaufmanFranco gown from the designer's Spring 2013 collection.  The garment featured ice white panels and a sheer back.  She accentuated the look with nude lipstick and black smoky eyes that seemed to smoulder.

With her 25-year-old boyfriend Casper Smart by her side, JLo worked the crowd in the body-hugging dress that accentuated her ample backside.  A sheer vertical side stripe suggested the absence of an undergarment.

jenny from the block and casper smart

In 'Parker,' Lopez is cast as a real estate agent who helps a double-crossed professional thief (Jason Statham) get revenge on his former partners-in-crime who shot him and left him for dead.

The film opens today in U.S. theaters.  Check out the movie trailer below:

Photos:  Judy Eddy-WENN