A few hours later, Oldman has nailed his scene, decompressed, and begun bantering naughtily with his castmates. ''Have you noticed,'' he asks Isaacs, ''how long my wand is?'' ''Yes,'' Isaacs volleys back, ''it expands in the warm, doesn't it?'' Radcliffe listens and grins broadly. He asks Oldman for advice on a tough role he's signed on for in Equus, a London revival of Peter Shaffer's 1973 play about a troubled stable boy, for which Radcliffe will appear naked eight times a week. ''You'll have to shave,'' Oldman tells him. Radcliffe's wide eyes open even wider: ''What — down there?'' Oldman nods, eyes closing. ''Especially down there.''

''I was worried,'' Dan says, grasping his elbows in his hands and pulling his arms in tightly at his sides — a study in British emotional reserve. ''Not because I had anything but complete faith in David Yates. But having done Equus, I thought I would go back and look at Potter and think, Oh, God, I would have done this so much differently now, because I've learned so much.'' So what did he think of his latest work? ''I actually didn't mind watching myself, for sort of the first time in five films,'' he says earnestly, rubbing his ever-so-slightly stubbly chin. ''I have got better. Thank God! I still see a lot of room for improvement, obviously. But I've started to see Harry rather than myself.''

Yates will return to direct Half-Blood Prince, and he promises a ''playful, very witty'' movie that will let Radcliffe ''stretch himself as a comic actor. He's a very funny young man.''

''You mention to somebody that you don't want to go to university, and they look at you like you're failing your kind,'' Dan says. ''I certainly don't think I'd enjoy it very much. I think I work much better educating myself.''

''All those stuuuupid headlines,'' Emma says, her lilting voice rising with indignation. ''You know, like 'Potter Gets Naked.' As if Dan was getting off his kit to become some sort of pinup, or something trivial and stupid like that. He's obviously kicked them all in the balls. It was really brave, and he pulled it off.'' So does this inspire Watson to redefine her image, too? ''I went for a couple of things this summer, but they didn't work out,'' she says. ''Which was a shame.'' Speaking for her young costars as well, Watson says she's ''really conscious'' that reaching escape velocity from the Potter series is critical right now: ''The next things we do will prove whether we're made for this business, and whether we really can act, as characters other than the ones we were cast for when we were so young.''