In Italy, a woman fears her sister has been kidnapped; Inspector Enzo Avolfi fears it's worse. They team up to rescue her from a sadistic killer known only as Yellow.

United by an uncompromising struggle as members of the infamous 1970s far-left terrorist group Prima Linea, fugitive couple Sergio and Susanna have become increasingly alienated from the real world. Their luck runs out when Susanna is captured and thrown in jail. Putting his life on the line, Sergio embarks on a radical plan... Loosely based on the memoir by Prima Linea's 'commander' Sergio Segio.