Paradise-1. Earth’s first deep space colony. For thousands of people, it was an opportunity for a new life. Until it went dark. No communication has been received from the colony for months. And it falls to Firewatch inspector Alexandra Petrova and the crew of the Artemis to investigate. What they find is more horrifying than anything they could have imagined.

Down there, beyond the deepest caves, below the crust and the mantle, there is another world. An old woman locked away in a Russian asylum has a secret - knowledge of a 500-year-old manuscript written by a long-dead alchemist that will show a passage to the mythical centre of the Earth. She knows it’s real because 50 years ago, she and a team travelled there. And only she made it back. Today, caving specialist Mike Monroe leads a crew into the world’s deepest cave in the former Soviet Union.

Bryan and Ellie Stockton hope they left behind their demons when they move to their idyllic new home in southern West Virginia. Above all, they want a fresh start for their young son, Derrick, who witnessed the tumultuous first years of their marriage—years that were rife with substance abuse, rage, and resentment. Their bright hope for the future is darkened when a child disappears from their neighborhood. The couple becomes suspicious of a reclusive resident with a degenerative brain disorder.

Psychologist Dr. Ophelia Bray has dedicated her life to the study and prevention of ERS—a space-based condition most famous for a case that resulted in the brutal murders of twenty-nine people. When she's assigned to a small exploration crew, she's eager to make a difference. But as they begin to establish residency on an abandoned planet, it becomes clear that crew is hiding something. While Ophelia focuses on her new role, her crewmates are far more interested in investigating the eerie, ancient planet and unraveling the mystery behind the previous colonizer's hasty departure.

On a sunny morning in June, Margaret Carpenter wakes up to find a new iPhone on her doorstep. She switches it on to find a text from her best friend, Charity Atwater. The problem is, Charity’s been missing for over a month. Most people in town—even the police—think she’s dead. Margaret and Charity have been lifelong friends. They share everything, know the most intimate details about one another…except for the destructive secret hidden from them both. A secret that will trigger a chain of events ending in tragedy, bloodshed, and death. And now Charity wants Margaret to know her story.