Artificial Intelligence (AI) has seen major advances in recent years. While machines were always central to the Marxist analysis of capitalism, AI is a new kind of machine that Marx could not have anticipated. Contemporary machine-learning AI allows machines to increasingly approach human capacities for perception and reasoning in narrow domains. This book explores the relationship between Marxist theory and AI through the lenses of different theoretical concepts, including surplus-value, labour, the general conditions of production, class composition and surplus population. It argues against left accelerationism and post-Operaismo thinkers, asserting that a deeper analysis of AI produces a more complex and disturbing picture of capitalism's future than has previously been identified. Inhuman Power argues that on its current trajectory, AI represents an ultimate weapon for capital. It will render humanity obsolete or turn it into a species of transhumans working for a wage until the heat death of the universe; a fate that is only avoidable by communist revolution.