Kanye West had the crowd going crazy at Saturday’s FYF Fest, but they went even crazier when he brought a very special guest out onstage: Rihanna.

image via Zelig Shaul/ACE/INFphoto.com

West wasn’t even supposed to headline the show; he replaced Frank Ocean at the last minute. Rihanna was sitting in the front row at the Los Angeles Sports Arena and Exposition Park, so West just handed her the microphone and they started to perform “FourFiveSeconds.”

Rihanna, who wore her curly hair up and a big, baggy sweatshirt, yelled to the crowd, "L.A., make some noise for my n---- Kanye!" E! Online reports.

They also performed their song "All of the Lights,” which features Kid Cudi.

West’s wife, Kim Kardashian, and some of her famous family members were in attendance as well. She posed for photos with Kendall Jenner and Kourtney Kardashian at the concert and posted them on Instagram along with some of West’s lyrics as captions.

image via Instagram from Kim Kardashian