The movie narrates the story of David Carr, an unemployed worker and member of the Communist Party of Great Britain. In 1936 he decides to fight for the Republican side in the Spanish Civil War, an anti-fascist coalition of liberals, communists and anarchists. Similar to George Orwell's experiences documented in Homage to Catalonia, he joins the POUM worker militia and witnesses first hand the betrayal of the Spanish revolution by the Stalinists, loyal only to the dictat of Moscow.