Go Behind the Scenes with ‘Silo’ Star Rebecca Ferguson for Episode 4’s Underwater Shoot

Armed only with a harmonium, Juliette swam through a world lost underwater in the fourth episode of “Silo” Season 2 — and that meant star Rebecca Ferguson spent a lot of time in the water tanks filming that particular episode.

“I dive a lot, when I can,” Ferguson says in a behind-the-scenes video from the day of the shoot. But that doesn’t mean that the day will be made easier. In fact, in many ways it was made even more difficult because Ferguson is playing someone who doesn’t know how to swim; after a lifetime in a bunker, Juliette has never spent this much time underwater.

“We built a set about 15 feet underwater, and we’re having some fun today,” episode director Michael Dinner said. “We built this tank from scratch. It’s like the second biggest water tank in the U.K., and we’ve just made it for this production,” director of photography Baz Irvine added.

“The set is so cool. It’s an entire environment of corridors, and what would have been left of people just evacuated,” Ferguson says of the underwater silo through which she’ll shortly be navigating. Watch the full behind-the-scenes video below.

Episode 4 found Juliette exploring another bunker after escaping her own, except this one is filled with color and decoration — and water. In it, Juliette dismantles a harmonium to use its bellows as a breathing apparatus to swim through a flooded room. As IndieWire’s Mark Blankenship wrote, “The props department built the piece from scratch, and they ensured it could function as both an instrument and as scuba gear. ‘We had divers look at it, and we had a harmonium specialist look at it, and we had the special effects department create all the elements so that they actually worked,’ prop designer Jonathan Norman said. ‘I wouldn’t want to use it myself underwater, but it is feasible that Juliette could turn it into a breathing device.'”

“Even if you’re comfortable in water, there’s so much going on,” Ferguson says in the video. “So one of the most important things is a quick, calming, meditative state.” Unfortunately for Juliette, that’s one thing difficult to come by in a Silo — harmonium or not.

New episodes of “Silo” stream every Friday on Apple TV+ through the season finale on January 17, 2025.