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Silo Season 1 brought us many mysteries. One of those was a disease that Peter Billings is suffering from. What is The Syndrome?

A good sci-fi story would be nothing without some mysterious illness that we don’t have right now. For Silo, it’s all about the illness called The Syndrome.

Peter Billings has it. He keeps it hidden, with only his wife knowing the truth. As Billings is promoted to Deputy Sheriff, his wife notes how the symptoms of the disease are getting worse. It’s clear that this is something he needs to report sooner rather than later, but he can’t do that. If he does that, he and his wife lose everything.

Those with The Syndrome can’t hold high positions. That includes the job that he has now. Billings is also worried that his daughter is showing signs of it, but his wife makes it clear that she is not. So, what is The Syndrome and why does it affect his job?

The Syndrome in Silo explained

The Syndrome is a disease that people have developed while being underground. Nobody really knows what it is, but it looks like stress makes the symptoms worse.

It’s also likely a disease that has developed due to the way people are living. Humans haven’t been designed to live underground for long periods of time. While the world has certainly been developed to ensure life continues until the planet is habitable again, it’s not ideal. People are under stresses that they shouldn’t need to be, and that is what could be causing The Syndrome.

There is no cure to it. It is a neurological disease that affects motor symptoms, so it makes sense why someone in the sheriff’s department wouldn’t be able to hold a job with it.

Billings is in some trouble, though. Sims knows that he has The Syndrome. Now Sims has something he can use against Billings to make sure Billings tows the line. That’s going to be important as Billings realizes that Bernard and Sims aren’t telling him everything.

MORE: Will Silo Season 2 happen?

What did you think of Silo Season 1? Share your thoughts in the comments below.

Silo is available to stream on Apple TV+.