The 57th Annual GRAMMY Awards - Show
Credit: Kevin Winter/WireImage

FYF Fest attendees in Los Angeles on Saturday were treated to a very special surprise during Kanye West's set. While performing "FourFiveSeconds," the rapper got none other than Rihanna to join in. But RiRi didn't come on stage for the song—instead, the singer sang the hook to the song from her spot in the audience, reportedly after West appeared to find her from the stage and she was handed a mic.

Fan footage shows the camera zooming in on Rihanna in the crowd as she sings her part of her hit single (which features West and Paul McCartney). "Make some noise for Rihanna in the crowd," West said to the audience after the performance to much applause. Watch the fan-shot performance here:

Later on, the Barbadian beauty joined the rapper on stage to sing "All of the Lights." See footage of it here: