Executive producer and novelist JP Delaney and production designer Jon Henson talk bringing Delaney's beautiful (but eerie!) vision to fruition.

The Girl Before's ultra-minimalist dream house harbors dark secrets.

Designed by uber-controlling star architect Edward Monkford (David Oyelowo), the home is a character in its own right, with customizable mood settings, questionnaires, and advanced technology to supposedly gather data on its occupants "to improve the user experience."

"The house has moods," co-writer and executive producer JP Delaney — who adapted his own novel for the miniseries — tells EW. "Depending on where you put the camera and how you light it, it can be austere, but it can be luxurious. It can be claustrophobic. It can be cocooning. It can be warm or it can be sterile."

It's also, according to Delaney, "Edward's brain made concrete." "And that's why he feels this controlling possessiveness for it, is that he's not just designed a house, he's designed a way of life and that feeds into his own psychopathy," Delaney explains.

Here, the author and production designer Jon Henson reveal how they brought it to life for the HBO Max miniseries (streaming now), which also stars Jessica Plummer, Gugu Mbatha-Raw, and Ben Hardy.

The Girl Before
'The Girl Before'
| Credit: HBO

1. Concrete Jungle

Elements of Japanese minimalism and brutalism transform what Henson thought, on the page, was a "very boring" white house. "To shoot in a white space with that many scenes, it just jumped out to me as a visual nightmare. Just dramatically and atmospherically, it would be really limiting to shoot in a white space, so I tried to talk [Delaney] out of that quite quickly and thank goodness he was really up for that," Henson says with a laugh. Instead, the production designer and his team — who built the set from scratch — went for a concrete structure with lots of glass elements. "Most of the finishes that you see that are concrete are scenically applied, so it's not real concrete, it's a scenic effect," Henson explains. "We made endless, endless sheets of architectural concrete that we applied." Also applied to several walls and floors are what Henson describes as "mottled stone," which he had imported from Italy. The result? "I think it's infinitely better than what I described," admits Delaney, "and it's very cinematic."

2. Stairway to Hell

Henson calls the floating stone staircase "a death trap." No one was allowed on it except during scenes, and even then, "whenever the actors are going up and down the stairs, they're attached to a harness so they wouldn't fall off." The building of the stairs themselves posed another challenge. "The main structure of the house is steel and then wood, and when we first built the staircase, we built it against the steel frame, but there was a small movement as you stood on it, there was just this millimeter of bounce in it," Henson recalls. "It just made you really feel uneasy, like you were going to fall off. So we built an enormous steel structure outside the set, just to accommodate the stairs." And, to further complicate matters, they built two versions of each of the individual steps. Henson describes it as "a steel strut that comes out with a tile cladding that slides off." "And then we made a rubber version of that, which slides on for the stunts that was finished to look like stone, but was in fact rubber, so it was safer for them to fall down the stairs," he says.

The Girl Before
Credit: HBO

3. Let It Glow

Henson treated the house as a character, with its own changing moods depending on the dramatic moment. "Sometimes I wanted it to feel like a sanctuary — calm and almost zen-like — but sometimes, more like a prison." Thanks to an idea from cinematographer Eben Bolter, he used Astera LED bulbs throughout the set to help accentuate the atmosphere. "They're basically tubes which you can dim the LED on so they don't get hot. You can dim them and you can change them very subtly in terms of their color," Henson says. "We built those lights through the whole set. I mean, every light pretty much that you see in the set is using that system, which meant that Eben could control it from an offset lighting desk and in a really subtle way — and sometimes, not so subtle."

4. Imitation Art

Since the series takes place in the house over two (eerily similar) timelines, Henson created two versions of a Japanese maple — real trunks dressed with fake leaves — to show different seasons. While the final effect is striking, it ended up being a lot of work for Henson. "On reflection, I created a monster. Sometimes in the middle of the day we'd be shooting Gugu in the morning, and then in the afternoon it would be Jess. We had a small window to change the trees, and they're quite big and heavy, so we had to devise quick systems to get them in and out. Yeah, it was quite a chore in the end," he admits.

A version of this story appears in the March issue of Entertainment Weekly, on newsstands Feb. 18. Don't forget to subscribe for more exclusive interviews and photos, only in EW.

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