TVGuide.com: Where do you stand with the next Potter film, Order of the Phoenix? [Isaacs plays Lucius Malfoy, the father of Harry's archrival, Draco.]

Isaacs: I'm shooting [State Within in Canada] all of next month, and then I go home, unpack, get the mothballs off the wig, stick it on and start waving my wand about.

TVGuide.com: A Potterphile pal of mine says fans are anxious to see how Order of the Phoenix handles the Battle of the Ministry, a "beyond huge" moment, I am told, in Potter lore.

Isaacs: I am, too. This is all as entertaining for me as it is for many of the fans. I turn up and they go, "OK, you materialize from here and you fly in over here, and then you point at this and it's going to explode...." I stand there with my jaw dropped. When I did [Chamber of Secrets], they said, "OK, there's going to be a little blue guy [Dobby the House Elf] walking next to you and then he's going to jump up to here...." [Laughs] On the first day of the first one I did, the first shot I had to do was storming out of a room, leaving the lovely Richard Harris (the original Dumbledore) and Daniel [Radcliffe, Harry]. [Director] Chris Columbus shouted, "OK, and then shut the door on your way out." I said, "Do I have to shut the door? I don't know what the rules are, but can I just wave my hand and the door shuts by magic?" Chris paused for a second and said, "Sure. If you like." That's when I knew I was going to have a great ride.

TVGuide.com: Lucius must be pretty fed up with always being bested by those pesky kids.

Isaacs: Well, I know that I go to prison for No. 6 [Harry Potter and the Half-Blood Prince], so I suspect that I have time to build up another deep well of bitterness that hopefully will burst out in No. 7.