For those Potter fans who can still vividly recall Jason Isaacs’ diabolically regal performances as Lucius Malfoy in 2002’s Harry Potter and the Chamber of Secrets, it is truly shocking to see the character so grubby and broken down in Harry Potter and the Deathly Hallows — Part 1. And Isaacs could not be happier about it. “One of the great privileges of being in the Harry Potter films for me is I’ve actually got to have a journey,” says the actor, 47. “Lucius has gone from being the most entitled, obnoxious, racist pig to a broken, emasculated shadow of a man — and that’s a fun thing for an actor to do.”

But how did Isaacs first decide to create Lucius’ rather unique bearing and haughty inflection? Blame Alan Rickman. “I got the part, and I thought, ‘I’d better watch what the first one was like,’” says Isaacs. “And then I realized to my horror that Alan Rickman was in the first film, and utterly brilliant. Nobody does sinister like Alan Rickman. I thought, ‘If I’m going to do something, it’d better be unbelievably extreme.’”

First up: Malfoy’s appearance.

“I went to the set, and they had this idea of me wearing a pinstripe suit, short black-and-white hair,” Isaacs recalls. “I was slightly horrified. He was a racist, a eugenicist. There’s no way he would cut his hair like a Muggle, or dress like a Muggle.” So Isaacs suggested instead that he wear a long white wig, and a particularly ostentatious wizard-like ensemble. “In order to keep the hair straight, I had to tip my head back, so I was looking down my nose at everyone. There was 50 percent of the character. I asked for a walking stick, which [Chamber of Secrets director] Chris Columbus first thought was because I had something wrong with my leg. I explained I wanted it as an affectation so I can pull my wand out [of the cane]. After a second’s thought, he said, ‘You know what, I think the toy guys are going to love you.’ He was completely right.”

Next: Malfoy’s accent. “There’s a particular art critic in England who has a voice like fingernails on a blackboard,” says Isaacs, who in real life has a far more accessible, slightly working class London accent. “I combined him with a teacher I thought was patronizing and sadistic when I was in drama school. To me what [the accent] smacks of is a sense of entitlement. I just wanted to find a voice that made him drip with the millennia that his family had been in power — complete disdain and contempt for anybody and everything else.”

But Isaacs’ accent did not go over so well after his first rehearsal. “Chris [Columbus] panicked. He asked David Heyman, the producer, to come to my dressing room and talk to me. So David came, and said, ‘I understand you’re doing a, uh, funny voice. What is it?’ I told him who it was a combination of, and he was slightly horrified.” Thankfully, a particularly important member of the Potter cast came to Isaacs’ defense. “We came down to the set to shoot,” says Isaacs, “and Chris said, ‘I don’t know. I’m not sure anybody really speaks like that.’ And Daniel [Radcliffe], thank God, said, ‘I think it’s really cool.’ Chris turned to him, and being the generous and playful soul that he is, said, ‘Well, let’s try it.’ I tried it, and it stuck. What was funny was, every time we’d do a take, Chris would come up and go, [in an American accent], ‘That was great, it was wonderful. Let’s just shoot one more, for safety, and if you could pull it back just, like, 80 or 90 percent.’” Isaacs laughs. “Which takes they used, I don’t know.”

For more on the Harry Potter Villains, including Voldemort, Severus Snape, and Bellatrix Lestrange, pick up this week’s issue of Entertainment Weekly.

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