Chris Martin is continuing to shake the post-split blues while diving into the promotional marathon behind Coldplay's Ghost Stories, and now he's taking to the big stages of festivals to sit in with some other huge names in rock n' roll.

At BBC's One Big Weekend festival in Glasgow, Martin joined Kings of Leon onstage for a performance of KOL's throwback favorite "Fans."

After introducing Martin ("the second most famous singer here today!"), Caleb Followill and the Kings launched into the hit off 2007's Because of the Times. The two frontmen sported matching acoustic guitars and black button-down/white t-shirt ensembles, so there was some pretty serous twinsies action going on during the impromptu jam. It may have been pouring in Glasgow, but the sunny sounds of KOL and Martin seemed to brighten up the crowd one tortured growl and G-chord at a time.