There's no doubt David "Mulder" Duchovny and Gillian "Scully" Anderson made the perfect pair of alien-hunting feds on The X-Files, but that doesn't mean they didn't need a little tweaking. You never see it on screen, but to compensate for Anderson's small stature, the show's crew devised a very simple method to keep her on par with Duchovny: the "Scully Box."

Anderson is approximately 5 feet 2 inches tall, while Duchovny is closer to 6 feet. That might not mean much in everyday life, but when you turn a camera on two people talking and there's a 10-inch height difference between them, it starts to look a little awkward. Mulder is either looking over Scully's head or forever dropping his chin to look down at her, while Scully is either looking up or staring at Mulder's chest.

There are a number of ways to correct this lack of visual balance. Peter Jackson famously used forced perspective tricks of all kinds to make his actors appear smaller or larger as needed on The Lord of the Rings, but that would be impractical for correcting a height difference of less than a foot. Hollywood has long employed a simple wooden box—known as an "apple box" on set—to correct such discrepancies.

For Anderson, the X-Files crew constructed a modified version of this, which you can see in the above photo. It's not high enough to make her as tall as Mulder, but it's enough to make filming conversations easier. It's also longer and wider than a typical apple box to allow for more movement, and the crew made copies so they could construct small walkways for her. The "Scully box" was also special in that it dropped the simple wood construction of an apple box for carpet-covered aluminum, which probably made for quieter steps.

In a 1997 interview with US Magazine, Anderson talked a little about the device—which she reportedly referred to as the "Gilly board"—and what it was like to use it. Oddly, she both denies standing on a box and then confirms it in the same quote, but that might just be because she didn't often refer to the device as a "box."

"I don't have to stand on a box. Sometimes when we're in a situation walking side by side, like up to a door to pull out our badges and say we're from the FBI, I have to step up onto something so that we're on the same level," she said. "I mean, I don't walk on boxes or have boxes attached to my feet. It's funny: Sometimes I forget I'm on the box. Like, I'll have this very serious moment in a very serious scene and I'll turn to the camera and fall right off the box."

(via Mental Floss)

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