Jersey Boys producer Graham King says he knew right away that Clint Eastwood was the perfect guy to direct the big screen adaptation of the musical stage show.

Speaking to Empire, the 52-year-old said: ''I knew he had this musical background and that's what made him perfect for 'Jersey Boys'.

''He'd been struggling to set up A Star is Born and within 48 hours of receiving Jersey Boys, he called me and said he loved it. He hadn't even seen the show at that point, so I recommended he go and check it out, so he did and that was when he decided he had to make it. It really was as easy as that.

''He works very quickly; it's been amazing to see his process. He first read the script in March and here we are in December with a finished movie.''