Chris Pine likens seeing 'Into The Woods' co-star Anna Kendrick singing to 'watching a martial artist', as he admits that the musical task for the production of the film was nowhere near as simple as it would appear.

Chris Pine in 'Into The Woods'
Chris Pine plays Cinderella's Prince Charming

It seems that none of the cast of 'Into The Woods' were particularly overwhelmed with confidence at the prospect of singing Stephen Sondheim's spectacular tunes - except perhaps Meryl Streep, who showed off her fabulous pipes back in 2008 with 'Mamma Mia!' Being more focused on acting than singing, it was nerve-wracking for the stars to say the least, and according to Chris Pine it didn't appear to get any easier once inside the studio.

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'Having now been in a recording booth and tried to do it myself, I realised how absolutely mindblowingly complicated it is to hit the notes, to give it the vibrato, to give it the emotion, to act it out with such precision', says Pine, who plays Cinderella's Prince Charming in the fairytale extravaganza. 'With what Anna's been asked to do, what Sondheim has given Anna's character Cinderella, it's like watching a martial artist or something. It's just profoundly cool.'

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Despite the difficulty in trying to perfect the music, it still seems that Pine - like much of the cast - felt extremely lucky to be given the opportunity to work on the stage to screen show. 'Rob Marshall [director] gave us all the music on an iPod, everybody's songs, and it's stunning', he says. 'It's really quite remarkable.'

Pine is the Charming-Not-Sincere royal heir in the film, which sees a selection of fairytale favourites including Cinderella, Red Riding Hood, Rapunzel and Jack and the Beanstalk brought to life in a story about being careful what you wish for. It sees all the characters venture into the forest with their deepest desires and subsequently being forced to deal with unforeseen consequences.

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'Into The Woods' hits movie theaters on December 25th 2014.