It’s completely different. By the time I did my bits [in the 'Potter' films], there’d already been three earlier movies, so everything was sort of operating like a slick, well-oiled machine. With Twilight, on the other hand, everything kept growing and changing and reformulating as we were working on it.

I was quite intimidated by Ralph Fiennes. I didn’t really talk to him while I was going Harry Potter and the only thing I did with him was when he stepped on my head. Then I went to this play and he was there. And this girl said, ‘you’ve worked with Ralph Fiennes haven’t you, Robert?’ and I was like, ‘well, no…’ and Ralph said, ‘yes, I stepped on your head.’ And that was the extent of our conversation.

[Ralph Fiennes] was like, ‘I stamped on your head.’

[Dan Radcliffe's] really an incredible kid. So young, about 15 or 16, but already a pro. Everyday he needs to work about 5 to 6 hours and then go back to study again. It’s like that for about 11 months. For the last 2 months, he even had a more serious schedule and he’s good at that. Now you can see his excellent acting in the released movie, and he did a really great job.

We had this bonding week at the beginning and I did a lot of improvising with Rupert [Grint] and he’s really, like he’s incredibly funny, but just as a real person, because he’s funny in the film obviously, but he can do - he’s like really versatile doing acting, and Emma [Watson] as well, she can just, she just does it, she’s an actress, she always has been and she’s just incredibly intelligent young person.

I did [get star struck] a little bit by the three main young [Harry Potter] guys when I first met them, it was kinda strange. We did this rehearsal week and it was kinda weird meeting these three rather iconic kids, and just talking to them normally. I couldn’t really get it out of my head that like ‘you’re Harry Potter,’ but that was strange, but not really, everyone was very friendly. It’s a very relaxed set.

I was so concerned about looking cool. It’s weird seeing [the Potter kids]. They are the most famous kids, I kept calling them famous. They’re on their way to becoming icons. I used to try to be moody and stuff. I’m really good friends with a lot of people from the film. It was a long time, I was doing it for eleven months.

I’m really good friends with Stan [Ianevski] and Katie [Leung]. We were all in the same boat as we all started new and I started on the same day as Stan. Stan and I did a lot of on-screen stuff together so we bonded well. All the cast are really nice but they are always busy, always, always on set.

I think Dan [Radcliffe] could steal anybody’s girlfriend. If I was a girl I’d go with Dan.

I’m a big fan of Michael Gambon. They were all really, really nice people and they treat it as a job. They don’t really have big egos or anything about it. There was one guy - Warwick Davis - he’s in Willow, and Willow is like my favourite film. I had one scene sitting next to him at the dragon task, and I had no idea what to say to him at all! He was the only person I asked for an autograph the whole way through it!

I get on really well with Katie [Leung], she’s a really cool girl. I don’t have many talking scenes [with her]. Most of my scenes, like big scenes, are just with Dan [Radcliffe]. I dance with her, and there’s a lot of scenes like holding hands and stuff like that. But I get on really well with her. She’s a nice girl.

I think, just in real life, [Dan Radcliffe's] just so far superior to me in terms of desirability, so he didn’t really have much of a competition with me. So there wasn’t really much joking around. I’d probably cry if he did. If I was Katie [Leung], I would definitely go out with him because he’s rich and famous, and I’m not really.

Sorry about my appearance. You’ve caught me on a dead day.

I’m not actually allowed to say anything about it, but [the return of Voldemort] is fantastic. That will be the most stunning sequence in the Potter series.

It was so easy for me to get into [the Harry Potter] universe.

[The cemetery scene] was the bit I was most looking forward to doing. You don’t really get to die that often, you know?

I think basically the characters have been pretty fully developed in the first three, and it’s just going to take another turn into being more of a thriller. It’s more boom, boom, boom, to the climax. I think it’s a much faster paced, action-oriented film than the others. I think that it’s a little bit darker, and they kill of key character. There’s always going to be a little bit of a twist - killing someone is always a bit of a shock.

Yeah, that whole sequence was pretty intense. They shot it right at the beginning—within my first week I shot in the maze. It was really difficult to translate all the things in the book that happened in the maze—like all these riddles and things—into film. It was almost impossible. The way Mike Newell did it was really good. He came up with the idea that in the maze it is just the fear and the darkness and the isolation that kind of drives all the competitors a bit insane. We were really hyped up. You are on 100% adrenaline and you’re starting this in the first week and you have just met all the other actors the week before and now you have to go crazy with them. That was pretty intense, but I think it was really the most fun, because it was really physical work. Shooting wands at each other was really fun. The swimming thing was pretty physical too. In fact all my scenes were kind of action scenes. They were all pretty physical.

I think the yule ball is more attractive to the girls who read it. I never really thought, ‘Oh, I get to go to the ball!’

I think the most embarrassing part of that was just the normal dancing. When the rock band comes. I think there was two days where the crew was like, ‘Just dance, just dance.’ So, you can’t, in a club or whatever. That was really awkward.

I had never done scuba-diving before, so I did training during the first week. I was in a tiny little tub that was a practice tank. I did not see the big tank until they first started shooting in it. It was about a hundred times the size of the practice tank and it was so much deeper, so that was sort of scary when I first got there, because you have to get used to all the pressure and things like that. I don’t know if you have been scuba-diving, but it is very different. I thought it was really easy in that little shallow pool, because it is, but when you are doing it in a really deep tank it is kind of scary at first. I got used to it quickly though.

Well, I haven’t actually died ‘live’ yet but I’ve been dead a few times. It’s strange, but it’s quite sort of relaxing. You feel like a bit of a therapist, because everyone’s giving you all their grief, and you’re just lying there listening. Yeah, it was quite nice, like no pressure after a couple weeks. I enjoyed it.

[I would switch roles with] Probably Harry [Potter]. I think. Not being arrogant or anything. I just think it’s a really intricate and it’s an amazing part. I think also when you don’t really have the opportunity to be guaranteed seven films when you’re growing up during the filming.

I knew the [Goblet of Fire] casting director from another movie which I did, and they wanted to see me for this part, but I was doing another movie over the casting period, so I ended up seeing Mike Newell and Mary Selway and Fiona Weir - who were casting at the time - before anyone else was seen for casting. And then, I went to do this other movie, and then the day I came back… I got a call back, and basically, that’s what happened.

I can’t say I was [a Harry Potter fan]. I wasn’t not a fan. I hadn’t read any of the books or anything. I read The Goblet of Fire when I was doing the other film, and I really liked that. I got through it in about two days. I’d say I’m a pretty big fan now.

I was actually having nightmares about [the premiere] for months in advance.

We had to do this scene looking like heroes diving into the lake. they had a stand-in doing perfect dives on the first take. Then Stan [Ianevski], Clemence [Poesy], And I tried, but none of us could dive in right, and we all looked really stupid.

There were a couple of times where you think you’re swimming towards a guy with a breathing apparatus and then you find it’s just something in the water and you’re like [imitates freaking out] and then you just know what to do and they film your stupid face just screaming underwater and then everyone starts laughing and it’s just like, ‘Ah, great!’

[Filming] was cool, it’s something different to anything I’ve done before and I hadn’t done a film or a part that big before so it was interesting. Working with like the best actors in England, the most famous actors, it was really fun, really exciting.

[Ralph Fiennes] could only shoot on certain days, so me and Dan [Radcliffe] tried to get bits of it done without him. And then when he came, because of the way the last bits were shot with Voldemort, a lot of it had to be rearranged. And so it was strange, because the first time I shot it I’d had about a month off through January and so I sort of psyched myself up to do this scene. And then when I re-shot it it was, I think we were filming the Yule Ball at the same time, so it’s kind of, you’re in this happy mode, and then you go in and you’ve got to be like… so I ended up sitting in a corner like eating mud and stuff… which didn’t really work.