Apple TV’s Silo has become one of television’s most absorbing sci-fi dramas by rooting its larger mysteries in deeply human questions. Across its first two seasons, the series has followed life inside a tightly controlled underground society where information is scarce, trust is fragile, and every revelation reshapes what its characters believe about the world around them. And what began as a story of survival within one silo has steadily expanded, with each new discovery adding weight and dimension to its central mystery.

That evolution continues in the highly anticipated third season. In the aftermath of Season 2, Silo begins to push beyond the immediate reality of a single underground community, moving toward a broader understanding of how many silos exist, who governs them, and why they were built in the first place. For Shirley Campbell, played by British actress Remmie Milner, that expansion brings fresh dangers, difficult choices, and an increasingly vital place in the story.

Shirley has emerged as one of the series’ most compelling presences, thanks in large part to Milner’s grounded, clear-eyed performance. Tough, intelligent, and fiercely loyal, Shirley is never defined by only one of those qualities. Milner has consistently brought a lived-in intensity to the role that makes her feel capable without losing the vulnerability beneath it, especially in a world where every decision can carry lasting consequences. And as Silo enters its next epic chapter, Shirley’s path feels more consequential than ever.

Ahead of Shirley’s return in Silo Season 3, Milner spoke with us about stepping back into the character, the series’ expanding scope, and the choices continuing to shape the character's journey.

Shirley has become such a memorable presence across the first two seasons of Silo. When you first stepped back into her world for Season 3, what felt most familiar about her, and what felt newly changed?

Remmie Milner: I’m so pleased that audiences have connected with Shirley in the way they have; she has been such a joy and challenge to play—I love her! Her outspoken, brave, and bold-hearted ways are truly admirable. And in Season 3, we still see this same fiercely passionate trailblazer of the Down Deep, and yet there is a new tenderness to her character which I’ve found so intriguing to explore. The storyline is full of twists and turns that force Shirley to open up emotionally and think outside of her usual rhythms, especially as the events and obstacles that she encounters are on a scale far larger than anything she has faced before.

The new season seems to push the story beyond survival inside one silo and into a much bigger understanding of the world around it. How does that expanded scope affect Shirley’s place in the story?

Remmie Milner: What is required of Shirley in season 3 is greater than anything she could have imagined, and she has to face it all head-on, which she does in true Shirley style; with pure courage and gusto. There’s a huge amount of new information to process, and the emotional impact of that weighs heavier on her than anything we’ve seen before, but she still manages to maintain the same dedication to the Silo’s survival and the need to seek out the truth in order to protect her people. Whatever the cost!

Shirley has always had this mix of toughness, loyalty, and sharp intelligence. Was there a particular side of her that you felt Season 3 gave you more room to explore?

Remmie Milner: Oh my, Shirley always has to think strategically—which is a comfort zone she thrives in—but this season she has to expand her skills and work closely with new people outside of her usual squad in order to survive. I am always blown away by her ability to speedily decode, process, and find a resolution in times of extreme pressure. It’s great to see her challenged even further this season and in such new ways—she is ever aware of a ticking time bomb that has been placed over their heads, and now more than ever, she has to act!

Morality is rarely simple in Silo, especially when characters are making choices without the full truth. For Shirley, how do you approach playing moments where the “right” decision is not always clear?

Remmie Milner: In the silo, we are constantly trying to figure out the deeper meaning of things or to uncover the true events that led to certain moments or decisions. And the best way Shirley can act to decipher the truth is to trust her instincts, then spring into action. She is a very impulsive person and can be unshakeable in what she believes in - but as we know in the Silo, things are never what they initially seem—so occasionally she will allow guidance from those she loves. And even then, she’ll put up a fight! In season 3, it’s interesting to see that while she still has her steadfast drive, she has learned to have a more logical head on her too… To zoom out, weigh up the options and then fully commit to whatever is needed for the greater good. She truly is such an inspiring woman.

The series has such a specific atmosphere, visually and emotionally. How much does the physical world of the silo help you find Shirley’s mindset once you’re back on set?

Remmie Milner: Ah, it’s a great question, because every time I’d be shown around the studios or introduced to new sets and special effects, I would be deeply impressed with the level of detail from all the departments who create the world of Silo. Shirley exists solely underground, and there is a very particular feel to that—through smells, dingier lighting, narrow passages, dripping pipes, even temperature - and they achieved it incredibly well. It is one of the most intricate sets I’ve ever been on, and it makes it feel like a playground for us actors. It would immediately land me in Shirley’s world and hugely added to the whole experience.

You’ve moved between sci-fi, thriller, fantasy, period drama, and stage work throughout your career. What does Silo ask of you as an actor that feels different from some of your previous roles?

Remmie Milner: I love performing in a whole range of work; if the storyline is captivating and the characters are nuanced and interesting, it is heaven to see how a world can build. What’s captivating about Silo is that it feels like a true mix of sci-fi thriller with drama at the heart of it. And in season 3, Shirley has more intimate scenes than we’ve seen before; these often felt like scenes from a play in which the dialogue has space to unfold at the pace it needs. So the main difference I would say is holding and developing the psychological and physical journey that Shirley goes on over four seasons; this was new to me and a challenge that I’ve adored finding the shape of.

As Shirley heads into this next chapter, what were you most excited for audiences to see in her evolution this season?

Remmie Milner: Shirley is an absolute firecracker, and we love her for it. I am super excited for people to see what surprises are in store and what secrets are revealed along the way this season. I had no idea we’d end up here when we first started filming back on season one, so it is truly a thrill to see it pan out and to now be able to share it with you all. Roll on, season 3!