Watch Jessie Mueller's Emotional Duet with Beautiful Surprise Guest Carole King

Carole King, who famously said she wouldn't see Beautiful, the Broadway bio-musical about her, surprised the cast on April 3 when she caught the show at the Stephen Sondheim Theatre. King said in a statement: “Jessie Mueller and company are fantastic and it was so joyous to be there. I couldn’t be more proud.”

King shocked everyone when she walked on stage during Jarrod Spector's curtain speech for the annual Broadway Cares/Equity Fights AIDS pledge drive. Watch the videos below to see the astonished reaction of Mueller and the stars as well as their emotional impromptu performance of "You've Got a Friend" with King.