该剧改编自休·豪伊所著同名畅销科幻系列小说，故事发生在一个反乌托邦未来，大约一万名人类在144层深的筒仓型地堡居住，他们被告知外面的世界因受到毒气感染而变得不适合人类居住，仅余的幸存者遂躲进地堡避难，并制订了规条来维持地堡中的新社会运作。

该剧讲述了四个18岁的大学新生室友的生活，分别由Pauline Chalamet、Amrit Kaur、Alyah Chanelle Scott和《贱女孩》的renee Rapp饰演。室友们在经历了成年、大学和新的性生活方式带来的挣扎和困难后，形成了深厚的友谊。

In the fourth season, Sisi challenges the best jockey in Bavaria to a grand horse race to save the family’s estate, Castle Possenhofen, after the death of her father. Back in her homeland, she comes across dark family secrets and ultimately must ask herself where she really feels at home.