Johnny Depp has admitted he finds acting therapeutic.

The actor, who's teamed up with long-time collaborator and director Tim Burton for the drama Sweeney Todd, said: "With every character you play there is some opportunity for therapy in a sense.

"There is exploration to some degree, exorcism in a way."

The new film is based on the hit Broadway musical and fans will even get the chance to hear Depp sing.

On the star's vocal chops, Burton said: "He did surprise me. It was better than I thought so that is always an exciting surprise."

Sweeney Todd: The Demon Barber of Fleet Street opens in the UK on January 25.

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