Then it was guest star time: Mark Ronson behind the turntables announced that they would go into "Uptown Funk" and Bruno Mars, his dancers and band took over for about a minute; when they said "Stop! Wait a minute!" it was Bey Time." She launched into her brand new song "Formation" - so brand new, it was released yesterday. The turned into a mashup between Bey and Bruno, and then towards the end, Chris Martin joined them for a bit of "Uptown Funk."