Anica Reljic, a former police inspector who now works in a call center, receives a call from Sonja Tosic, a rich single mother who wants to know the identity of the person who is threatening her on the phone. As Anica investigates the threatening calls, she realizes that they are connected to a criminal group from her past life.

She tries to warn Sonja, but Sonja disappears, prompting Anica and Tiana, Sonja's rebellious daughter, to go in search of her. They soon discover that Sonja may be the key to uncovering the truth behind an environmental scandal rocking the country: the mysterious poisoning of three boys.