Craig says that the sets often required a more “theatrical, operatic” scale than the book described, although they were as faithful as possible to Rowling’s intricate descriptions. The only serious departure, Craig says, was the location of Professor Snape’s (Alan Rickman) death. In the book, he dies in the Shrieking Shack; in the film, he dies in a boathouse that resembles a Gothic sanctuary. “We did ask Jo Rowling if we might [change] that. She absolutely agreed that we could,” he says. Craig made the boathouse of “90 percent glass, and the reason for that was that it seemed magical that Hogwarts was on fire above it—or big sections of it—and there was a sense of the flame from the fire above being reflected in the glass, also reflected in the water, which in turn reflected in the glass.” The team wanted to give Rickman “a suitable place to die. Alan appreciated it, actually, and said so very kindly afterwards,” Craig says.

Another place that Craig says he thought could use a “certain amount of exaggeration” was the Room of Requirement, which appears in the film stuffed to the beams with mountains upon mountains of furniture. “The fact that they were looking for a tiara—this tiny little jewel of an object—in something so massive and complicated just made the task all the more impossible.” And to create that effect, Craig relied on good old-fashioned elbow grease: “We [modeled] it first with little blocks of Styrofoam and composed this kind of mountainscape, and then we made another model with dolls’ furniture, and then finally replicated it full size.” To prepare for the scene, fellow Oscar nominee and set decorator Stephenie McMillan had been buying furniture for months upon months, gathering the team’s “stockpile,” Craig says, but “even then, of course we cheated and the center was a series of big plywood boxes, just to bulk it up. The furniture was just one or two layers on top of that.”

For Gringotts Wizarding Bank, “everything conspired to make the goblins look very small, and to make the bank look—as banks do—very dignified and solid and important,” Craig says. That meant lots of imposing pillars, which actually are “just paper”—as was the marble floor. “We had quite a considerable marble-making factory,” he says, laughing. As for the chandeliers, he says, “they were 16 feet from top to bottom. We made the bottom half physically and then the top half was put in as a C.G. addition. So it wasn’t just whole sets that got extended; it was individual things, like chandeliers, that got extended by visual effects.”

Ironically, in the aftermath of the films, some of the sets that were rendered in C.G.I. have had to be physically re-created. For instance, for the Warner Bros. studio tour in London, Craig says, “Diagon Alley had a green screen at both ends in the later films. On the studio tour, to see Diagon Alley with a green screen at the end is pretty disappointing, and so we have painted a backing in forced perspective, so that at least looking one way down the street, the illusion is complete.”

As the franchise ends, the interest in Harry Potter shows no signs of flagging: Time Warner’s 5 percent increase in its fourth-quarter net income has been attributed to Potter mania, and the franchise has plenty of awards-season buzz. Craig says, “It just speaks to the great popularity of the books,” but admits, “I am extremely surprised. Really. Eight films, 10 years. The fact that it’s still getting attention, being nominated, is phenomenal, really. It’s very, very extraordinary.”

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