The story starts because of one journey. Seven people who have never met before climb aboard the same ride that goes into a seemingly endless tunnel. Despite the countless trials, corpses that mysteriously appear, past acquaintances that returned from the dead and an unseen danger threatening to swallow them whole, it's as if they are trapped in an enclosed space where there is no escape.

Lin Jiaying, who has lived with her sister under warlord rule, watches helplessly as her sister is persecuted by Warlord Ma Shijie. Discovering her sister was a member of Ho Meizi's Special Forces Group for Women, Lin Jiaying joins the group, endures rigorous training, and forms close bonds. As she faces internal conflicts, she begins to question and uncover the secrets of the organization.

The story starts because of one journey. Seven people who have never met before climb aboard the same ride that goes into a seemingly endless tunnel. Despite the countless trials, corpses that mysteriously appear, past acquaintances that returned from the dead and an unseen danger threatening to swallow them whole, it's as if they are trapped in an enclosed space where there is no escape.