SWEENEY TODD star Johnny Depp is set to disappoint fans hoping to see him reprise the role on the Broadway stage, insisting he'll only tread the boards "when hell freezes over". The actor makes his big screen singing debut in the movie adaptation of Steven Sondheim's musical about a barbaric London barber. But Depp found singing a traumatic experience - and has no intention of repeating it any time soon. He says, "When hell freezes over. That's very flattering, but no, I think I am done with singing."