Tom Felton has heaped praised on co-star Jason Isaacs for his performance as Lucius Malfoy.
Felton is set to return as Draco Malfoy in the final Harry Potter movie; Harry Potter and the Deathly Hallows. which is going to be split into two.
The pair have played father and son in the series of movie and Felton has revealed that he has enjoyed watching Isaacs create his character.
Speaking to the New Zealand Herald the actor said: "Jason plays an evil sod so beautifully well. 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.
"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."
Harry Potter and the Deathly Hallows: Part One opens is released on November 19.
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