From "Viva la Vida" to "Viva Las Vegas." Coldplay's lead singer Chris Martin surprised fans on Saturday when he was spotted singing at a karaoke bar in Las Vegas while disguised as a tourist.

The singer was unrecognizable in a frumpy suit and a red-haired wig as he handed out red balloons Chris Martin has gone from "Viva La Vida" to Viva Las Vegas! During a couple's wedding photo shoot ...