Watch a bunch of Broadway stars dump freezing-cold water on themselves.
The Oscar winner joined the cast onstage to sing a special encore finale.
The casts of A Gentleman's Guide to Love & Murder and iLuminate were also on hand for the weekly outdoor concert.
The Tony-winning production's "Girl" offers an inside look on the differences between standing by and leading the show nightly.
The best of London's West End theater scene is honored at the annual ceremony.
The musical features the Academy Award-winning music and lyrics of Glen Hansard and Markéta Irglová.
Here's a look back at the musical's award-winning run on the Great White Way.
Irish tunes will be heard during the show's nightly pre-show concert.
The Book of Mormon, The Scottsboro Boys, and Once are all up for the coveted Best New Musical honor.