Rupert Grint has played Ron Weasley on film since he was 12. Rupert is 17 now, about 5 feet 10 and no longer in school. The changes in Rupert -- as well as 16-year-old Daniel Radcliffe, who plays Harry Potter, and 15-year-old Emma Watson (Hermione Granger) -- mirror the changes in the characters the three teenagers portray.

In "Harry Potter and the Goblet of Fire," which opens in theaters tomorrow, Harry must deal with dragons, sea serpents and Lord Voldemort. He, Ron and Hermione also must try to stay best friends while being very emotional teens. The PG-13 movie has some scary scenes offset by more than a few laughs.

At a news conference at a fancy London hotel and in a conversation with Bridget Byrne, Rupert talked about starring in the movies about the Hogwarts wizards. He looked suitably bashful when pretty Emma, apologizing for making Rupert "really uncomfortable," said she hopes that in the seventh and final Potter book, Hermione and Ron "end up together."

Do you think younger kids will be scared by this movie?

I've got younger sisters, and they didn't seem to be that affected by it. It's a little bit scary as it goes on, but I think it will be all right for them.

Were you scared reading any of the books?

When I read the first one, maybe. But . . . I enjoy 'em. I actually like the scary bits.

Why do you feel you were perfect casting for Ron?

I've always liked Ron. He was always my favorite character [when] reading the first book. I suppose I could relate to certain things. We've both got ginger hair and both got quite big families and are both scared of spiders.

Have you had to come anywhere near real spiders when making these movies?

In the second film the big one, Aragog, was a big puppet. I didn't mind that, really, because I knew it wasn't real!

What was the toughest thing you had to do in this movie?

We had to do this training course and learn to [scuba] dive. I'm not really the strongest swimmer, so that was quite scary sometimes. Being underwater was sort of claustrophobic. But luckily, in the end, we didn't have to do that much because they had dummies.

If you were able to do magic, what would you use it for?

To pass my driving test. I'm learning at the moment. It's going all right, but it would be easier just to be able to do that.

The 17-year-old actor has grown into his role as Ron Weasley. But there is no hope for this costume in

"Harry Potter and

the Goblet of Fire."Rupert Grint, at a "Potter" premiere, says he has always liked Ron.