James Bay's powerful Let It Go is becoming a cultural moment. Not only has a dance routine set to the stirring ballad gone viral, but during last night's (Oct. 4) Cambridge concert, Bay reached new heights. Singer-songwriter and musician Ed Sheeran, who is having quite the moment of his own from the heat of his latest x LP, came out to assist on a collaboration of the song. Both musicians took their guitars in their hands and delivered a must-see performance.

"Ed doesn't have to turn up and guest on mates' records or gigs," Bay says of the experience, which you can watch in-full below. "But he's a real musician who just really loves to play. What's awesome for the rest of us is that he's so generous with that." Previously, Bay has enlisted many of music's other fine vocalists and musicians to join him on stage, including Elle King (who recently commanded the No. 1 Alternative Song in the U.S. with Ex's and Oh's) and The Rolling Stones' Ronnie Wood.

Let It Go is ripped from Bay's debut full-player Chaos and the Calm. You can grab the album on Apple Music.

[PHOTO CREDIT: Courtesy of Republic Records]

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