Leighton Meester is Star Trek Sexy

Leighton Meester is pure perfection in head-to-toe YSL at the premiere of Star Trek at the Grauman’s Chinese Theatre on Thursday (April 30) in Hollywood.

The 23-year-old Gossip Girl, who lightened her locks earlier this week, was accompanied to the event by costar boyfriend Sebastian Stan. The couple hit up Katsuya restaurant after the premiere.

Leighton wore a fierce gray YSL dress with bow details on the back. She finished off her look with Neil Lane jewels and YSL cage ankle boots and clutch.

15+ pictures inside of Star Trek sexy Leighton Meester…