WARNING: this article contains major spoilers for Shift and Dust and may anticipate elements of Silo Season 4.

After three seasons of Silo, we have learned to see Silo 18 as the great problem inside the system. It is where Juliette refuses to accept the answers she is given, where the lies begin to unravel, and where an entire community gradually realizes that its history is not what it was taught. But in Hugh Howey’s books, another community came dangerously close to breaking that mechanism decades earlier. Silo 40 did not simply rebel. It did something far more dangerous: it apparently figured out how the system worked and began dismantling it from within.

That is why, after discussing the possible spin-off and the importance of Silo 40, there is an even better question left to ask: how did it manage to fool Silo 1?

The most accurate answer is frustrating and fascinating at the same time: we know a great deal about what happened, but Hugh Howey never fully explained how it happened. And now we know why. The author is working on the very story that should fill this enormous gap left between Shift and Dust.

It begins when a silo simply disappears

In Shift, we learn that a little over a year before Donald is awakened again, Silo 40 had effectively vanished from the network controlled by Silo 1.

The suspicion was that its head of IT had rebelled. That makes sense: within the structure created by the founders, very few people possessed enough technical knowledge to understand the communications system and, more importantly, realize that their silo was part of something much larger. But he apparently did more than simply disconnect the phone.

Silo 40 seems to have interfered with its communications antenna, established contact with other communities, and sabotaged the mechanisms Silo 1 used to control it. By the time Donald is informed about the scale of the problem, this is no longer one rebellious silo. Eleven silos have already fallen outside Silo 1’s normal communications network. This is where Silo 40’s rebellion becomes far more dangerous than anything we initially saw in Silo 18.

The fundamental principle of the entire project was isolation. Each population was supposed to believe it was essentially the only community left, with no knowledge of who lived next door and certainly no possibility of speaking to them. The architecture of the silos itself is based on that idea: fifty parallel human experiments, supervised by a single central command, with no possibility of comparison.

Silo 40 breaks that rule. One unhappy population can be controlled. Eleven populations exchanging information begin to form a network. And a network can realize that the problem is not inside any of those silos. It is the people controlling them.

Silo 1 had a way to erase entire communities

One of the most brutal revelations in Shift and Dust is that Silo 1 was not designed merely to observe the other communities. It can eliminate them.

If a silo becomes impossible to recover, there are safety mechanisms capable of triggering its destruction. The system was designed to preserve the project, not necessarily the people living inside it. That detail changes everything when we think about Silo 40.

The first response was not to send soldiers, negotiate, or try to win the rebels back. It was to activate the termination protocols. But something had been altered. The safeguards had been sabotaged, and Silo 1 could not even confirm whether its commands were working.

That explains why the crisis became so serious. Thurman, Victor, and Erskine had to be awakened, and Anna also became involved in the operation. This was no longer a local uprising. It was a structural failure of the entire system. And there is one crucial difference between what normally happens to a condemned silo and what ultimately happened to Silo 40.

Donald ends up authorizing a military operation to bomb it. Think about what that means: the men who built a system capable of remotely destroying its own communities came to the conclusion that, in this case, they could no longer trust the system itself. Silo 40 had done something extraordinary.

But who taught the other silos how to disappear?

This is exactly where Howey stops explaining.

We know Silo 40 opened a forbidden line of communication. We know other silos began disappearing from the network. We know safety mechanisms were sabotaged. What we do not know is exactly who did all of this, how much each community understood, or whether there was a truly coordinated rebellion. And perhaps the most interesting question is another one: what did Silo 40’s head of IT actually discover?

Because cutting off communications is one thing. Realizing that Silo 1 exists, understanding where the orders come from, locating hidden systems, and discovering mechanisms designed to kill your own population requires an entirely different level of knowledge. Someone opened the black box. And then began teaching the neighbors.

The even stranger connection to Silo 17

The story becomes more complicated when we get to the nanobots.

In the books, the famous “good nanos” are fundamental to explaining how certain characters survive seemingly impossible situations. Hugh Howey later confirmed that Silo 17 received a huge dose of these beneficial nanobots from Silo 1 and added one extremely important detail: Silo 40 helped make that happen. That helps explain Solo’s survival in that environment and, later, Juliette and the other inhabitants’ ability to cross the outside world. But once again, we are left with a massive narrative gap.

How did a silo that was supposed to be isolated and under attack manage to interfere with an operation controlled by Silo 1 itself? Howey never showed us. This is probably one of the biggest untold stories in the entire Silo universe.

And we know the bombing did not solve everything

For a long time, it would have been perfectly reasonable to end the story by saying Donald ordered Silo 40 bombed and the rebellion ended there. Except Hugh Howey himself has already revealed that it did not. Silo 40 was destroyed, but some of its inhabitants survived and made it to other silos. Again: how? We do not know.

Perhaps they escaped before the attack. Perhaps there were routes or mechanisms we still do not know about. Perhaps other silos in the rebellious network helped them. Perhaps what Silo 1 interpreted as destruction was never quite what it seemed.

Any answer now would be speculation. And that is precisely the material Howey intends to explore when he returns to Silo 40.

The real revolution began before Juliette

This also changes the way we look at Juliette.

She remains the central character in the saga and the person through whom we finally watch the system begin to collapse. But she was not necessarily the first person to understand that the world around her was a lie.

Decades earlier, someone apparently realized that the best way to defeat Silo 1 was not to climb the stairs and open the door. It was to break the information system. Talk to the people you were forbidden to talk to. Compare versions. Shut down surveillance systems. Prevent the authorities from knowing what was happening. And, above all, make other communities realize they were not alone.

Perhaps that is what makes Silo 40 so fascinating. Silo 18 gave us the story of rebellion. Silo 40 may give us the story of organized resistance.

And now we need to watch Season 4 carefully

Apple’s adaptation has already changed enough from the books that it is impossible to assume all of these events will reach television in exactly the same form. Season 3 made that definitive by transforming Daniel/Troy, Helen, Victor, and the very origins of the silos into something far more emotional and detailed. But there is now one number worth watching: 40.

If Season 4 mentions a community that suddenly stops responding, an unexpected communication, a failure inside Silo 1’s systems, or an interference Daniel/Troy cannot explain, we may not simply be watching another piece of the finale.

We may be watching the beginning of the next story. Because Juliette still has to bring down the system. But someone may have started breaking it long before she did.