On Friday it was reported that Kanye West would be replacing rapper Frank Ocean last-minute as the headliner for FYF Fest this weekend in Los Angeles. While many Frank Ocean fans were both bummed and befuddled by the sudden drop-out, it looks like festival attendees may have actually gotten a two-for-one deal in the wake of Ocean's departure.

Last night, Kanye performed his set at the event, and during his solo performance of "FourFiveSeconds," the artist's stripped-down collaboration with Paul McCartney and Rihanna, the rapper actually spotted the Barbadian beauty in the pit of the crowd. (Hey, even pop stars want to catch a festival show sometimes!) Upon the sighting, which we suspect is similar to spotting a unicorn in the wild, a smiling Kanye had festival crew members pass her a microphone so she could sing along to her parts of the track's hook live from the audience. "Make some noise for Rihanna in the crowd!" the rapper shouted after the song. See below:

Later in the evening, Rihanna joined Kanye yet again—this time on stage, wearing an over-sized hoodie—during the latter's performance of the My Beautiful Dark Twisted Fantasy album single, "All of the Lights." Unsurprisingly, the impromptu on-stage team-up of two of music's biggest mega-stars had the festival crowd going absolutely bonkers. You can check out some fan footage of the surprise appearance and performance below:

Currently, it's been reported that both Kanye West and Rihanna are busy working on new records (potentially titled SWISH and #R8, respectively). Well, here's hoping for a studio collaboration from the duo!

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