Amidst a heated political climate, the opposition leader is killed in what appears to be a traffic accident. When a magistrate finds evidence of a government cover-up, witnesses start to get targeted. A thinly-fictionalized account of the events surrounding the assassination of Greek politician Grigoris Lambrakis in 1963, Z captures the outrage about the military junta that ruled Greece at the time.

On December 12, 1969, a bomb kills 17 people at the Piazza Fontana national bank in Milan, Italy, marking the beginning of the Years of Lead. Local anarchists are scapegoated for the massacre by police and the media, but a lone prosecutor uncovers a conspiracy of far-right groups, corrupt secret services, and other interests that seek to undermine democracy.

Bastien is twenty years old and has been an activist for five years in the main extreme right party. When the presidential campaign begins, he's invited by his superior to commit even further. Initiated into the art of decking himself out like a politician, he starts to dream of a career, but old demons surge forth...

Denmark, in the near future. One year after a major bomb attack in Copenhagen, political radicalization has intensified and ethnic tensions are increasing. As next year's parliamentary elections approach, in which nationalist leader Martin Nordahl hopes for a landslide victory, Zakaria becomes involved in a radical organization, where he befriends Ali.