Adam Levine has revealed he almost didn't join The Voice - the US talent series that has become a summer hit. The Maroon 5 singer is one of the show's four celebrity judges, which include Christina Aguilera, Cee Lo Green and Blake Shelton. But Levine, 32, says he was "extremely hesitant" to join The Voice. In an interview with The Hollywood Reporter, he says: "Sure, at first you think: 'A freakin' singing competition?' But it really is different. And, as soon as you watch it, you see that." Pictured: Bottom L-R: Cee Lo Green, Blake Shelton, Paul Telegdy, Bob Greenblatt, Mark Burnett, Adam Levine and Christina Aguilera Splash News and Picture Agency does not claim any Copyright or License in the attached material. Any downloading fees charged by Splash are for Splash's services only, and do not, nor are they intended to, convey to the user any Copyright or License in the material. By publishing this material , the user expressly agrees to indemnify and to hold Splash harmless from any claims, demands, or causes of action arising out of or connected in any way with user's publication of the material.