Director Tim Burton and actor Johnny Depp's relationship has spanned almost two decades, their first picture together was Edward Scissor hands in 1990, and together they have brought memorable, if some what slightly strange movies, to the big screen.

Sweeney Todd

Sweeney Todd

Their adaptation of Stephen Sondheim's hit Broadway show Sweeney Todd: The Demon Barber of Fleet Street is the first must see movie of 2008.While Tim Burton delved into the darkness of Gotham City and Depp into the Jack the Ripper murders in From Hell this is possibly the grimmest subject matter the pair have tackled.

Depp stars as Benjamin Barker, a man unjustly imprisoned for 15 years on the other side of the world, who escapes back to London with a vow of revenge, opposite Helena Bonham Carter as his obsessively devoted accomplice, Mrs. Nellie Lovett.Adopting the guise of Sweeney Todd, Barker returns to his old barber shop above Mrs. Lovett’s pie-making premises, and sets his sights on Judge Turpin (Alan Rickman) who, with help from his nefarious henchman Beadle Bamford (Timothy Spall), shipped him off on a trumped-up charge in order to steal his wife, Lucy (Laura Michelle Kelly), and his baby daughter from him.

Mrs. Lovett tells Todd that his wife poisoned herself after Judge Turpin took advantage of her. But when a rival barber, the flamboyant Italian Pirelli (Sacha Baron Cohen), threatens to expose Sweeney’s real identity, Todd kills him by cutting his throat.

Soon Todd's revenge is the only thing on his mind to the detriment of everything and everyone else.

But director Tim Burton defends the sinister material:'By having more blood, it actually made it a bit less graphic, because sometimes when you don't show stuff it has a tendency to be more real and disturbing.

'So we just decided to go for it in the spirit of those old melodramas.'

However dark subject matter about slaughter, revenge and passion se to a background of showtunes, yes you may be surprised to hear that this is a musical, didn't put off the Golden Globe voters as the film picked up Best Motion Picture for a Musical or Comedy and Best Actor in Musical or Comedy for Depp and could be in the running for an Oscar when the nominations are announced in the coming weeks.

But there is some good news for the director, musicals are back in a big way with Chicago winning Best Picture in 2003 and Hairspray was a surprise hit in the summer of 2007.

But Burton was faced with a major problem his leading man had never sung professionally before.

'It was a challenge to see if I could do it. You've got to try something once and give it a shot,' Johnny said.

'It's a bit like jumping into cold water, there's no preparing you just do it. So I tried my best not to disappoint Tim or Stephen Sondheim.'

While the director and his adoring fans, who lined up outside Leicester Square at the European premiere, seem happy with his performance the musical is a genre of film that Johnny may not be returning to.

'It took a while to get used to it, because I had to do so much of it I had to get used to it. I've never done it before and I'll never do it again.'

But Burton seemed to embrace the lack of singing experience casting acting talent over vocal ability and Alan Rickman also found himself outside his comfort zone.

'I got a singing teacher and worked hard. But it's very enjoyable too, everybody should sing people should not do it because people tell them they can't everybody can sing.'

While this may be Johnny's sixth collaboration with Tim Burton this is the fifth time that actress Helena Bonham Cater has worked with the director, and she had to audition like everyone else.

'I was a bit like Simon Cowell," joked Burton. "But, to be fair, she put in a beautiful performance. She was right for the role - that made it very easy to cast her in the end.'

But for the British actress this was a role that she longed to play: 'It's one of the best written roles for women ever. I loved it from the age of 13. I think I've always wanted to be Mrs Lovett,' she said.

'Filming was so fantastic because it is so well written and I loved the music.'

Like many of the cast Helena had to sing in front of Sondheim.

'It was like completely sick making but I got through it. He is actually fantastically relaxed,' she explained.

However it was not the musical aspect of the filmmaking process that bothered the younger stars it was coming face to face with the behind the movies they had grown up watching.

'Terrifying, I feel so proud thought, I was so nervous,' Jamie Campbell Bower, who plays Anthony Hope who rescues Todd from the sea, said about working with Burton and Depp.

'They have their own special relationship but the are very giving people and I'm very proud and happy that I got to be a part of it,' he continued.

Sweeney Todd is Jamie's first film role and he was comfortable with the musical genre: 'I had sung since I was about eight years old so I guess it wasn't as difficult as it could have been, coming with no singing, but I still found it difficult because it's Sondheim and it's just so rhythmically complex.

Like Jamie Ed Saunders, who plays Toby, did find his first movie a challenge: 'It was hard, there were so many story lines going on adding to the complications, but it was still great fun to do.'

Sweeney Todd has won the critics over in America as the successful partnership between Depp and Burton rumbles on when asked what makes the partnership work Johnny said: 'Tim is what makes it special, I love to work with him.'

Sweeney Todd is released 25th January.

FemaleFirst Helen Earnshaw

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