Leighton Meester Performs with Weezer at the Hammerstein Ballroom in NYC!

This Halloween, Leighton Meester skipped out on trick-or-treating to join forces with Weezer at their Hammerstein Ballroom show in NYC! During a special performance of the band’s first single “(If You’re Wondering if I Want You To) I Want You To” she traded off lead vocals with frontman Rivers Cuomo. Plus, Nat Wolff (of the Naked Brothers Band) joined in on guitar! Check out the concert footage now!