This Saturday, New York City's annual Global Citizen Festival drew wide crowds for its headliners: festival curators Coldplay, Pearl Jam, Beyonce and Ed Sheeran. The free, one-day festival which promotes the charity Global Citizen to help fight inequality and poverty, boasted an array of surprise duets from Coldplay and Ariana Grande, Beyonce and Ed Sheeran, Sting and Common. The most shocking collaboration of all was the one which included Beyonce, the queen of pop and Eddie Vedder, the king of grunge, teaming up for a rendition of Bob Marley's "Redemption Song."

Although the "Halo" singer was a billed artist for the festival, she stunned the audience when she took to the stage during Eddie Vedder and company's headlining set. She sat beside the Pearl Jam veteran, equipped with his acoustic guitar and the two singers swapped verses and shared the song's chorus for a remarkable rendition of "Redemption Song," a track Pearl Jam hasn't played live since 1995. The performance was backed by a video of Nelson Mandela delivering a speech concerning the well being of humanity and overcoming extreme poverty while Vedder stuck his guitar licks and Beyonce spewed harmonies under the words of the former South African president, NME notes.

Pearl Jam wrapped up their 12-song set with a "Rockin' in the Free World" cover, originally by Monsanto singer Neil Young, as well as a gentle rendition of John Lennon's "Imagine." According to Rolling Stone, the group performed the Young track earlier in the week with Stephen Colbert providing background vocal assistance.

Beyonce dropped by as a surprise guest once before during the 2014 Global Citizen Festival when she shocked fans watching her husband, Jay Z's, set where the two performed "Holy Grail" and "Young Forever." During Beyonce's personal set during this year's festival, she provided her own surprise duet with Ed Sheeran. The X singer graced the stage to join Beyonce for a track he's covered numerous times, "Drunk in Love."

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