1844. Karl Marx is 26 years old and living with his wife Jenny in exile in Paris. He is habitually in debt and plagued by existential anxieties. When he first meets the slightly younger factory owner’s son Friedrich Engels he dismisses him as a dandy. But Engels, who has just published a study on the miserable impoverishment of the English proletariat, has long since begun to distance himself from his own class. The two like-minded men become friends and soon inspire each other to write texts in which they seek to provide a theoretical foundation for the revolution they believe must come. Their goal is no longer to merely interpret the world, but to change it. Fundamentally. Resistance on the part of conservative forces and internal power struggles within the political Left only serve to spur them on.
Raoul Peck describes the origins of the international Socialist movement, the emergence of the Communist League and its founding document, the Communist Manifesto. At the same time, the film paints a portrait of two impetuous young men who passionately believe in the vision of a humane society and the revolutionary power of the abused and oppressed.