'Harry Potter' director looks back, and ahead

As he and Harry enter the home stretch, director David Yates is visibly exhausted. "I'll tell you why," said the man behind "Harry Potter and the Deathly Hallows: Part I," which opens Friday. "It's been a marathon - four years and four films, back to back, and so I am tired at the core."

Not that there isn't a bright side - like being part of the most successful movie franchise ever. Or the fact that everyone can now stop worrying about the stars outgrowing the J.K. Rowling stories. "They don't have to get any younger," he said of Daniel Radcliffe, Emma Watson and Rupert Grint. "We can take the pills out of the tea we used to give them to keep them small."

GRADUATING FROM HOGWARTS In fact, Radcliffe, Watson and Grint - Harry, Hermione and Ron - seem more than ready to burst out of the series that has made them world-renown teenage millionaires. "Dan has such energy and enthusiasm, he'll pull himself into another stage," said Yates. "And Emma is igniting - she can do anything she wants. She's incredibly bright, she's independently wealthy, she has a great academic career, she could do anything. And Rupert is a really talented actor."

APPREHENSIONS ABOUT DIMENSIONS Part II of "Deathly Hallows" ("98 percent in the can," the director said; it will be released July 15, 2011) is expected to be in 3-D. So was Part I, briefly. "We were very cautious and nervous about the whole notion," said Yates, who added that none of Part I was expressly shot in 3-D. "We started to convert part of it, and I said: 'It's going to be great for big sequences, but this movie's intimate - it's three people in a tent.' (So what on earth is 3-D going to bring?" He had, he said, "a very difficult conversation with the studio, and I said, 'This isn't going to work,' and they came around."

THE WEIGHT OF WIZARDRYThe responsibilities of bringing a book series as successful as "Potter" to the screen was never lost on Yates. "The expectations are always madly sky high," he conceded. "But Steve Kloves, who has adapted seven of the eight movies, said to me at one point: 'Listen, don't worry: No matter what you do, no one's going to take the movie seriously. So just relax.' And he has based that on years of experience."

But the sense of ownership that filmmakers generally feel toward their work doesn't really apply with Harry, said Yates, the last of the four directors to tackle Potter. "I feel like I'm looking after this national treasure," he said of the series, which seems to have put more English actors to work than Shakespeare. "Every day I make a hundred decisions - I'm eating, sleeping, dreaming Harry Potter. But in a weird way I can say, 'This belongs to the audience,' to the extent that when I finish next year and come out of it, I'll feel like a first-time filmmaker."

DARK FORCES, DARK THEMES That "Deathly Hallows" is the darkest "Potter" yet, Yates said, is reflective of Rowling's book, which includes the rise of the "pure blood" movement within the magical world, and even a torture scene involving Hermione. Any suggestion of current events, Yates said, is purely intentional. "It's all in Jo's book," he said of Rowling, "and there's something really compelling about that being in a children's story."