Harry Potter's Oliver Phelps on why the Marauder's Map scene was the most important to him

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Fred and George Weasley have a lot of memorable moments in the Harry Potter series, whether it’s wreaking havoc on Professor Umbridge with a fireworks show in the Great Hall or the violent fates they suffer in Deathly Hallows.

But Oliver Phelps, the man behind George Weasley, points to a moment in the third film, Harry Potter and the Prisoner of Azkaban, as his most meaningful — the scene where George and Fred gift Harry with the Marauder’s Map, a magical map of Hogwarts that also tracks the movements of its denizens.

“Of all the scenes we did in all the eight films, that’s the one I treasure more than anything,” he says. “Because when we got the part, my grandfather started reading the books to try and understand what on earth we were doing, and he always said that scene was when you see our characters for the first time in their own element.”

Phelps says he really took his grandfather’s advice to heart and poured a lot of preparation and care into the scene. “I still remember to this day calling my granddad from the hotel and telling him how it went and everything,” he explains. “Unfortunately, he ended up passing away before the film came out.” Still, Phelps said he was pleased the scene came out the way he felt his grandfather had always envisioned it, and because of that, it still holds a lot of sentimental value to him.

The actor also notes that director Alfonso Cuarón also took inspiration for the scene based on Phelps and his brother James’ actual relationship. “We’d done a few things earlier in the year with Alfonso when we met him, and he liked the way we always cut each other off,” Phelps notes. “We did that quite a bit, so he got the script slightly changed so Fred and George were always finishing each other’s lines off, which we ended up doing in the film.”

Though the scene isn’t quite as effects-heavy as many Potter sequences, Phelps always says the scene was full of magical trickery. When Fred and George first intercept Harry, they notice him trudging through the snow in his invisibility cloak thanks to his footprints. Phelps explains the footprints weren’t CGI, but actual hydraulic steps that dropped in the artificial snow on cue and could reset for multiple takes.

The scene also required three versions of the Marauder’s Map — a practical prop, not all that different from recreations you can buy at Harry Potter theme parks; one with a green screen on the front of it to place effects onto; and another that had a physical exterior that unfolded into a green screen for more effects to be added in post.

But even more important to Phelps than the map was his wand. The scene marked the first time he got to see and use George Weasley’s wand. “He’d never needed one before that in any of the films,” he explains. “I remember seeing it and literally just before we started filming, the prop guy gave me the wand and I was looking at this thing and then I just hear, ‘Ok, we’re rolling.’ And I’m like, ‘Hang on, hang on, I’m looking at my wand!'”

A magical (and sentimental) scene indeed.

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