Extreme guitarist Nuno Bettencourt revealed he once shared a brief songwriting session with Paul McCartney. During his video chat with Rick Beato, Bettencourt recalled McCartney helping him along with a new tune during the 2015 Grammy rehearsals when Bettencourt was backing the former-Beatle, Rihanna, and Kanye West for their performance of their hit single, “FourFive Seconds.”
Ultimate-Guitar.com quoted Bettencourt remembering, “I just hear his voice, 'What's that you're playing? Ooh, I like that; it sounds expensive!' (Laughs) I'm sweating now, he's talking to me, and I'm sweating. He goes, 'What do you got for the chorus?' Because I said it was just a little verse. 'What do you got for the chorus?' — and I'm (thinking) like, 'Don't tell me I'm writing a f***ing song right now with Paul McCartney, please don't tell me that's happening.'”
He added, “And I (thought), 'Y'know what? F*** this,' and I go, 'What would you do for the chorus?' And he just starts singing (in) Paul McCartney falsetto. And I'm (thinking), 'Oh my god, this is incredible, I'm writing (with Paul McCartney)' — and then Kanye (West) comes over and interrupts us.”