I can't imagine how intimidating it is to take the reins of a Harry Potter film, but you've done it once and it was an incredible success. How does it feel coming into your second Potter film?

David Yates: It's great fun, actually, and I enjoyed it so much last time which is why I came back. We had some guests on set about two weeks ago and the first thing they said after they'd had a tour around the studio was that they couldn't believe that it was a film set and everyone seemed to be smiling all the time. There's a really positive atmosphere here, so it's a great working environment; everyone feels very committed to their particular craft and what they're doing. There's a terrific vibe and while you're creating, and working and trying to deliver story, that atmosphere really helps.

I'm having probably even more fun on this one than I had on the last one. The last one was quite intense because of the scale of it; these are big films to make, and they just inevitably require you to multitask a bit, and I think I've gotten used to that multitasking approach to directing. Which is now, for me, quite an adrenaline rush; I think I really enjoy having two or three sets going at any one time.

I've got a terrific second unit director called Stephen Woolfenden who I worked with on Order of the Phoenix and we have a very close working relationship. We're like twins, really. Traditionally second unit directors go off and do their own thing, but Stephen and I work really closely together and that's terrific.

I've also brought a new D.O.P. called Bruno Delbonnel who shot Amelie and A Very Long Engagement. He's French and he's got a really good sense of humour. So we're having a good time so far!

What does he bring to the film?

DY: It'll be warmer than the last film. Order of the Phoenix was dealing with teenage angst and it was dealing with that period in life where you start to rebel a wee bit and you're struggling against authority and all of that, while this film is much warmer and much more romantic. It'll have a much richer and more romantic feel to it than Order of the Phoenix which was a bit darker and bit more intense.

Is it fair to say there's more character as well?

DY: There is. The sixth book essentially deals with the politics of romance. We're tuning into the spirit of all of that and because the characters are all getting a little bit older and the actors are all getting a little bit older, there are more nuances, I think, in the relationships. There's a lot more character development in this one.

With Daniel Radcliffe and Bonnie Wright.

You've added a couple of scenes to the film that aren't in the book.

DY: Yes. In the sixth book Jo talks about the Death Eaters attacking, kidnapping and striking terror into communities and she plays that idea backstage in the book. You read about it but you don't experience it. We wanted to bring that experience to the fore for the audience so they kind-of felt what it was like and they could actually see what the Death Eaters were doing. We've introduced two moments in the film where we see the Death Eaters do what Jo actually described them doing, but off the page as it were.

In the book Jo describes the collapse of a Muggle bridge. We never see it but she relays it. I just thought it'd be really cool to see that, again just to make the audience feel what the Death Eaters are doing to the Muggle world. It's such a cool thing to experience and it's quite frightening. So again we just took it straight from the book, the notion of it, and we've just put it into our story at the beginning. None of our principal characters will be involved.

The other scene is at the beginning at the railway station; traditionally these films have always opened at the Dursleys' and there's a pattern, the audience is used to that. Steve came up with this notion of breaking it. You sit down, you see the WB sign, you hear the tinkly-tinkly stuff and then, oh, it's the Dursleys. It's that comic Dursley bit at the beginning and then we'll get on with the story. Steve came up with this notion that after Order of the Phoenix Harry's in this quite intense, dark place and he's riding the trains to free his brain a wee bit and he meets this really attractive waitress who he really likes. You immediately set up the notion that suddenly these characters are a bit more sexualised if you like, they're aware of the opposite sex. Their hormones are kicking off and I thought it was a really charming, lovely idea.

But the scene in which the new Minister of Magic visits the Muggle Prime Minister didn't make the cut?

DY: Scrimgeour isn't in this particular film, no. We struggled to keep him in. It's great scene in the book where he goes to see the Prime Minister. We loved that and it was in and it was out and it was in and it was out again.

We have brought Quidditch back, because I love Quidditch. I wanted to get Quidditch in the last film but we were so overstuffed with things that it was really hard. There's a moment where you're making a film where you want to go, "We want to do this, this, this and this," and fiscal reality and schedule reality kicks in and so we were determined to get Quidditch back this time. And it's a really fun Quidditch sequence. Kind-of comedy Quidditch!

From what I understand Dan isn't as thrilled as you are about the return of Quidditch!

DY: [laughs] Dan's not particularly pleased with Quidditch [being back] because he has to sit on this broom for five hours a day! If you've ever sat on one of these brooms, and I've never, it just looks incredibly uncomfortable. They're not the most seat-friendly contraptions.