The book tells about the life and work of Georgy Valentinovich Plekhanov, an outstanding Russian Marxist. Plekhanov's name in the history of Marxism and the revolutionary movement is inextricably linked with the spread of the teachings of Marx and Engels and the creation of a Marxist workers' party in Russia with an ideological struggle against the populism of philosophical revisionism and liquidationism. Plekhanov's Marxist works were a valuable contribution to the theoretical thought of scientific socialism.