Sting will join No Doubt for a special collaboration at the Global Citizen Festival, which returns to the Great Lawn in New York's Central Park on Sept. 27. Details on the "must see" performance remain under tight wraps, though celebrated live event and television producer Ken Ehrlich has offered some insight into how the team-up came to be. "In this case, it was pretty organic," explains Ehrlich, who joins the team to produce this year's show. "It came from No Doubt. We talked about a couple of possible people to do something with. As soon as we mentioned Sting, they loved that..."