The singer/songwriter and American Idol judge lit candles on his piano and blew them out dramatically one by one as he suggested fans should put down their cellphones for a moment and just listen to the music in the dark - but he had no idea how dark it would become.

The Somebody Like You hitmaker recalls, "I put the mic down and 'Clink, clonk, clonk...' I couldn't see anything... and I'm the only guy (onstage); I'm playing a solo song. The roadie's running out, he's got the flashlight out... I did not think that through."