Nicola Sacco and Bartolomeo Vanzetti, two Italian immigrant anarchists, are arrested in Massachusetts in 1920 and charged with murdering a paymaster and a guard during a shoe factory robbery in South Braintree. The film lays out the case against them and the case for their innocence: shaky ballistics evidence, a jury and judge hostile to their politics and their accents, and a trial that unfolded during the Red Scare, when anarchists and immigrants were already suspects by default. Their conviction draws protests across the world, from labor unions to intellectuals, all arguing that the men were being punished for their beliefs rather than the crime. Appeals stretch on for years while public pressure builds, but Massachusetts executes both men in 1927. The film treats the case as a hinge point in American labor and immigrant history, one still cited as an example of a justice system bending under political fear rather than evidence.