Silo seasons 3 and 4 have already been confirmed, and there are plenty of massive questions waiting for answers when Apple TV+’s hit sci-fi series returns.

Based on Hugh Howey’s series of novels, the show has always been built on big mysteries about the origins of the titular underground Silo that 10,000 people call home. But as Sheriff Juliette Nichols (Mission: Impossible’s Rebecca Ferguson) and her allies have discovered more about their vertical metropolis, sinister forces (led by Silo mayor Bernard Holland, played by The Shawshank Redemption’s Tim Robbins) have closed ranks to protect its secrets.

Season 2 storylines have involved Juliette being trapped in one of the many other Silos, her former colleagues in Mechanical rebelling against the powers-that-be, and plenty of revelations to make you query everything you thought you knew about Howey’s ingeniously realised world. Of course, as with Apple TV+ stablemate Severance, every answer the show has delivered has raised another pertinent question – so here are 10 burning questions Silo season 3 needs to answer. We can’t wait…

***Warning: spoilers from Silo season 2 ahead***

1. Have Juliette and Bernard survived?

At the end of season finale “Into the Fire”, Juliette Nichols (Rebecca Ferguson) finally makes it back home to Silo 18. Before she can make it through the airlock, however, embittered mayor and head of IT Bernard Holland (Tim Robbins) turns up brandishing a gun. Their tense conversation is subsequently interrupted when the Silo’s sterilisation procedure activates, engulfing the corridor in flame. Will they make it out alive?

It’s pretty much guaranteed that Juliette will return – she’s the main character in the show, Ferguson is an executive producer, and showrunner Graham Yost alluded to his plans for the character in season 3 in an interview with The Wrap.

Bernard’s fate is a little more up in the air. The character dies at the end of Wool (Hugh Howey’s first Silo novel and the inspiration for the first two seasons), but the show has been known to play fast and loose with the source material before. In other words, all bets are off.