"Jason plays an evil sod so beautifully well," sniggers Felton. "He's perfect as a villain. But it's scary how he has the ability to be telling you a showbiz story one minute and as soon as they say 'camera rolling' he snaps into this horrible [git], who grabs my ear and does all sorts of twisted things.

"I enjoy seeing these amazingly friendly people turn into such horrible characters," he adds, teasingly. "Ralph Fiennes is the worst: it's an eye-opener playing alongside him, because he's such a gentle soul, who's quite calm and measured in his conversation, but then he instantly turns into this twisted, nasty creature the moment we start filming."

"I don't know what qualities I brought that made them think I could play this satanic child, but I am very grateful they chose me to play the bad guy rather than the goody," he grins. "I revelled in the fact I could vent my day-to-day frustrations through this Hitler-like child; it was actually quite therapeutic and enjoyable."

"Also, I'll finally get to leave the blond hair behind! Dying my hair blond and generally looking like a complete freak became rather tedious," he admits, sighing. "It was the same with holidays: not being able to go in the sun, so that my skin remained pale, became a real pain. Instead of being able to sit on the beach I had to sit under sun umbrellas whenever I went on holiday. So, for me, the best thing about this ending is the opportunity to finally go on holiday and, for the first time, be able to swim in the sea, out in the sun,"