Mafia is a six-episode crime series, drawing inspiration from actual events. It unfolds the transformation of Sweden in the 1990s, evolving from a relatively tranquil nation untouched by organised crime into a land marked by intense gang conflicts and violent shootouts. The series also delves into the life of the notorious gangster Radovan "Jakov" Jakovic, chronicling his journey from poverty to wealth.

Against Jakov is a police officer called Gunn Thörngren, a dedicated officer who recognises that the income from cigarette smuggling will build a full-fledged mafia in Sweden. However, her battle isn't limited to combating an infamous criminal gang; she also finds herself at odds with her own law enforcement agency, which fails to grasp the gravity of her perspective. Gunn faces a total lack of understanding regarding her belief that the cigarette trade should be treated with greater seriousness than armed bank robberies.

Mafia touches on a critical time in Swedish history, the consequences of which still echo today. The series takes viewers back to a time when acts of violence such as shootings were unusual, almost unthinkable, but where cigarette smuggling, in particular, became the prelude to a new type of organised crime.