A perfect life crumbles for Billy Halleck, a successful lawyer who, after a traffic accident in which he hits an elderly gypsy woman, finds himself in the crosshairs of a curse of revenge. Although he manages to escape the legal consequences of his actions thanks to his influence, the gypsy, on her deathbed, curses him with a simple yet terrifying phrase: "Thinner!" From that moment on, Billy begins to lose weight alarmingly, unable to stop the process, even when he tries all sorts of diets and methods to regain his figure and health.
As his life falls apart, so do his relationships; his wife begins to worry and is drawn to other men, while Billy becomes increasingly obsessed with his fate and the betrayal that led him to this situation. As extreme thinness devours his life, Billy realizes that the curse is not just a matter of appearance, but has a strong psychological impact that drives him into a state of despair.
Desperate to regain control, Billy embarks on a mission to find the source of his torment, confronting ancient gypsy magic and discovering that the consequences of his actions can be far more terrible than he ever imagined. In his quest for redemption, he finds himself caught in a deadly game where every decision matters and his time is running out.