Ellen Pompeo & Kirsten Dunst: NYE at The Cosmopolitan!

Ellen Pompeo steps out in a black suit at The Cosmopolitan‘s Grand Opening and New Year’s Eve Celebration held at Marquee Nightclub on Friday (December 31).

Also attending the party: Kirsten Dunst, who made a pit-stop at Del Taco on her way to Sin City.

Jay-Z and Coldplay treated celeb guests, including John Mayer, Emmy Rossum, and Kellan Lutz, by hitting the stage and performing.

The night before, Ellen attended the opening of Marquee with husband Chris Ivery.

20+ pictures inside of Ellen Pompeo, Kirsten Dunst, and Emmy Rossum at The Cosmopolitan’s Grand Opening and NYE Celebration…