Silo season 2 episode 9: What is the safeguard? Explained

Last week's Silo season 2 episode 9 ended in an intriguing cliffhanger with the Algorithm's voiceover talking to Lukas Kyle about a certain "safeguard" that could be triggered if the need arises.

With only one episode left before season 2 of Apple TV+'s hit dystopian sci-fi drama ends, the stakes are higher and fans are eager to understand the secrets of the Silos, including what the "safeguard" means.

If the series stays true to the storyline of Hugh Howey's books, which it has been so far, the "safeguard" in Silo season 2 episode 9 symbolizes an extreme protocol that can be used to thwart a rebellion and preserve the order within a Silo. It could mean a self-destruction protocol that could wipe out an entire Silo in the event of a successful rebellion, like what happened in Silo 17, as seen in the season 2 premiere episode.

Disclaimer: This article may contain some spoilers for Silo season 2 episode 9. Reader's discretion is advised.

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The meaning of "safeguard" in Silo season 2 episode 9 explained

From secret tunnels and doors to fake VR graphics and the existence of other Silos, there are many things the citizens in the Silos don't know about the underground bunker complex they are living in. Lukas Kyle in season 2, however, is one of the people who found one of the best-kept secrets of Silo 18—a tunnel located under Silo 18.

Silo season 2 episode 9 saw Lukas discovering layers of secrets about the Silos with the help of Salvador Quinn's coded message. He deciphered the message that mentioned the other Silos and how the founders created a "safeguard," which reads:

"The founders didn't build a single Silos. They built fifty. And they created the safeguard."

The safeguard was mentioned again when Lukas heeded Quinn's message to find the tunnel at the bottom of Silo 18. As seen at the end of Silo season 2 episode 9, Lukas found the tunnel and when he tried to access the vault door, the Algorithm talked to him. It said that there were only three people who discovered the vault before him, Salvador Quinn, Judge Mary Meadows, and George Wilkins.

The Algorithm also told him not to speak about what he saw and what happened down there, or else they wouldn't have any choice but to initiate the "safeguard."

When the Algorithm asked Lukas if he knew what the "safeguard" meant, he said that he did. Based on what the Algorithm told Lukas in Silo season 2 episode 9, it implied that the safeguard is a threat.

While the word "safeguard" wasn't mentioned in the Hugh Howey's Wool novels that the series is based on, it did mention a termination protocol. If triggered, the protocol would release poisonous gas inside the Silo, wiping out all the citizens inside it.

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Silo showrunner confirms that the "safeguard" is a "big, bad thing"

Silo showrunner Graham Yost told Collider after the showing of Silo season 2 episode 9 on January 10 that the mysterious safeguard protocol poses a grave threat to Silo 18 citizens, further hinting at a dark tone in the season finale. He said:

"Episode 9 ends with, 'Do you know what the safeguard is, Mr. Kyle?' 'I do.' Well, we don't know what it is, but we're going to get an idea in the next episode, and it's not good. It's not a good thing. It's a big, bad thing."

Yost also admitted that Silo fans who have read the books will know what the term safeguard means, which circles back to the destruction protocol that could wipe out the entire Silo.

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Catch Silo season 2 episode 9 and all the previous eight episodes of the second season only on Apple TV+. Episode 10 and the season 2 finale drops on the streaming platform this Friday, January 17, 2025.