Apple TV+ on Monday announced that Rebecca Ferguson’s Silo has been renewed for another two seasons. The streamer also shared that the fourth season will be the last chapter.

Based on a trilogy of novels by Hugh Howey, the third and fourth season will allow the makers to narrate the entire story completely. Graham Yost serves as the Executive Producer and Showrunner.

The show tells the “story of the last ten thousand people on Earth, their mile-deep home protecting them from the toxic and deadly world outside. However, no one knows when or why the silo was built and any who try to find out face fatal consequences.”

Speaking about the upcoming seasons, Yost in a statement said, “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.”

Ferguson also expressed her excitement and said, “I’ve loved every minute of bringing Juliette to the screen and I am immensely proud of what we’ve all created with Silo since the first episode.”

Silo’s season two cast also features Tim Robbins, Common, Steve Zahn, Harriet Walter, Chinaza Uche, Avi Nash, Alexandria Riley, Shane McRae, Remmie Milner, Billy Postlethwaite, Rick Gomez, Clare Perkins, Caitlin Zoz, Tanya Moodie and Iain Glen.