Silo season 3 release date speculation, cast, plot, latest news

The final episode of season 2 gave us death, destruction, and a fair few answers to our questions – before that last scene dropped a gigantic hint about where the story is going to go next.

Previously speaking to RadioTimes.com, showrunner Graham Yost confirmed that we'll find out more about how exactly the silos came to be in future seasons, saying: "You'll also see something in the final episode that gives you just a hint of where we hope to go in the rest of the story, which is finding out how this happened."

Anyone who's read the books will know the best storyline is still to come, with a very important congressman and journalist being introduced at the end of season 2.

Season 3 will see the second book in Howey's trilogy, Shift, adapted, and send us back in time to when the silos were first built.

So, after Silo was renewed for season 3 (which is currently filming) and for season 4 (which has already been written), here's everything you need to know about what's set to happen.

Silo season 3 release date speculation

Silo season 3 does not yet have a release date but we're estimating it could be released in mid-2026.

That's based on the gap between seasons 1 and 2 being released, which was a year and six months. If this timeline continues, we'll be looking at around May 2026 for season 3.

Showrunner Yost has also confirmed that seasons 3 and 4 will be filmed back-to-back this year, with only a short break in between – so hopefully there won't be too long to wait between the final two seasons.

Seasons 3 and 4 will allow for the full Wool trilogy to be adapted, with Yost previously telling TheWrap: "OK so now the cat’s out of the bag, we can talk about it. I would say five weeks into Season 1, we knew we were going to do the whole thing."

In December 2024, Apple TV+ officially confirmed that Silo had been renewed for seasons 3 and 4.

Showrunner Graham Yost said at the time: "It has been a richly rewarding experience to adapt Hugh’s epic novels with our partners at Apple and we are thrilled to have the opportunity to bring this complete story to the screen over the course of four seasons.

"With the final two chapters of Silo, we can’t wait to give fans of the show an incredibly satisfying conclusion to the many mysteries and unanswered questions contained within the walls of these silos.'"

Matt Cherniss, head of programming for Apple TV+, added: "The addictive, inventive and moving ‘Silo’ has had us hooked since day one and we’ve loved watching global audiences become equally enamored with the world that Graham Yost has created.

"As we look to seasons three and four of this ambitious, character-driven sci-fi series – which will conclude Juliette Nichols's journey and complete Hugh Howey’s epic trilogy of novels – we can’t wait for everyone to experience more of the show’s powerful performances led by the incomparable Rebecca Ferguson, as well as the unexpected twists, turns and surprises that we’ve come to expect from this very human story."

As Cherniss confirmed in his statement, Silo will end after season 4.

Who could be in the cast of Silo season 3?

While the cast of Silo season 3 hasn't yet been confirmed, we'd expect the majority of the season 2 stars to return – barring those who didn't make it to the end alive, that is.

We'd expect returns from:

• Rebecca Ferguson as Juliette
• Avi Nash as Lukas Kyle
• Common as Robert Sims
• Harriet Walter as Martha Walker
• Chinaza Uche as Paul Billings
• Alexandria Riley as Camille Sims
• Shane McRae as Knox
• Remmie Milner as Shirley
• Clare Perkins as Carla
• Billy Postlethwaite as Hank

The season 2 finale also introduces Jessica Henwick as Helen and Ashley Zukerman as the congressman – and it's been confirmed that they'll return as regulars in season 3.

We're not expecting to see the return of Tanya Moodie as Judge Meadows or Iain Glen as Dr Pete Nichols after their deaths in season 2.

The fate of Bernard Holland, played by Tim Robbins, was also left up in the air at the end of season 2. We're also unsure whether we'll see the return of Steve Zahn's Solo.

What will the plot of Silo season 3 be?

Judging from that final scene, Silo season 3 will cover the book Shift, which details how and why the silos were built in the first place.

We won't give too much away here but the book Shift starts hundreds of years before the events of Silo seasons 1 and 2, and follows the perspectives of congressman Donald Keene and a man named Troy.

It then takes us back up to the present day and includes some of Solo's backstory, as well as a new character named Mission.

It massively expands the world of Silo, giving an insight into what happened to result in people having to live underground, allowing a few different plot lines to converge in the final book.

It means we might step away from Juliette's story for a little bit as we're transported back in time – but don't worry, we'll get back there and her story will be concluded.

Yost told TVLine: "In the book Shift, Juliette doesn’t appear until like the last page, right? It’s about this silo [No 18], but it’s also the origin story of the whole silo project.

"I would say that we have Rebecca Ferguson playing Juliette, and she is not just going to be in the last scene of the season."

Yost also previously told RadioTimes.com that he's excited to answer some of the mysteries that have already been established – including how the residents of Silo 17 (Solo's silo) were able to step outside without a suit on.

He said of the concept of the Safeguard, which was introduced at the end of season 2: "The concept is in the books, the fact that there is this other silo, this controlling silo, they're the ones that people speak to when they go in the vault, or if you go down to the bottom of the silo and that there is this thing called the safeguard, which is that this other silo can kill a silo within minutes, essentially by poisoning them.

"And why would they do that? How? What is going on? And then we start to peel back a little bit. In Silo 17, they all went outside without cleaning suits on, and they didn't die for quite some time – what happened? Well, that's a big mystery. That's something eventually we hope to get the chance to answer."

Yost added: "We always wanted that feeling that it's not a bad society in a silo - people have got jobs, they've got food, they've got medical care, you know... But there's something weird about fertility, and who gets to have children, and there's other things. The Pact is kind of weird..."

How many episodes will be in Silo season 3?

We don't know for sure yet but we'd expect there to be 10 episodes, just like seasons 1 and 2.

We also don't know which writers and directors will helm the episodes in season 3 (although we'd expect showrunner Yost and potentially writers including Jeffery Wang and Ingrid Escajeda to return).

Is there a trailer for Silo season 2?

Not yet! In the meantime, check out showrunner Graham Yost explaining the end of season 2:

Silo season 2 is available to stream now – you can sign up to Apple TV+ here. Hugh Howey's Wool Trilogy is available to buy now.

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