During Ocean's performance of "Close To You," Pitt held up a phone to his ear and pretended to have a conversation.
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Brad Pitt just joined Frank Ocean on stage. Now, that was a surprise. #fyffest2017pic.twitter.com/xt38K4SpcH
— deray mckesson (@deray) July 23, 2017
Pitt wasn't the only big name in attendance on Saturday -- director Spike Jonze apparently filmed the whole thing.
INSANE. Frank killed it. Spike Jonze visuals were on another level
— Landon (@LandonGerrits) July 23, 2017
In awe pic.twitter.com/gIX6YhzKla
spike jonze shooting frank ocean apparently pic.twitter.com/DEPs9GcjsJ
— dan vasmon (@danvasmoon) July 23, 2017
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While Pitt and Ocean might seem like an unlikely pair, the actor has been a big fan of the singer for years. In fact, Pitt credited Ocean's music for inspiring him post-divorce.
"I find this young man so special," Pitt toldGQ Stylein May. "Talk about getting to the raw truth. He's painfully honest. He's very, very special. I can't find a bad one."
Last month, Ocean made it known the love is mutual, when he wore a shirt with Pitt's face on it during his performance at the Northside festival in Denmark.
See more from Pitt's tell-all interview in the video below.