In a dystopian future where overpopulation has led humanity to impose a strict one-child policy, a group of seven sisters, identical in appearance, is forced to live in hiding to survive. Raised by their grandfather in a small apartment, each sister is named after a day of the week and they take turns living the life of a single person, named Karen Settman, interfering with the daily routine to avoid raising suspicions.
However, their fragile lifestyle is threatened when one of the sisters, Monday, fails to return home after going out alone. Desperate to know her whereabouts, the other sisters plunge into a world of mystery and danger, facing government forces that seek to control the population at any cost. As they delve deeper into a web of conspiracy and betrayal, they uncover dark secrets about their own existence and the oppressive system that surrounds them.
As a struggle for survival unfolds, they are forced to join forces and confront not only their own fears but also the cruelty of a regime determined to eliminate them. In an exhilarating game of cat and mouse, the sisters will have to find a way to save themselves and free their family from a terrifying fate, pushing the confrontation to the limit in a race against time filled with action and shocking revelations.