Out of Time is an exploration of the possibility of timelessness. Time, it is argued, might not exist. This claim is defended by attacking three reasons to think otherwise; to suppose that time must exist. First, that our concepts of time are immune to error in a special sense: no matter what we discover about the world, we will all just continue to agree that time exists. Second, that the loss of time is incompatible with what we know from science and, third, that time’s absence would do extreme violence to our self-conception as agents. In response, a range of empirical studies are used to show that everyday concepts of time are not immune to error. It is likewise argued that recent developments in physics may in fact recommend the loss of time. And, finally, a viable notion of timeless agency is rebuilt using only causation. The book is ambitious in its scope, unyielding in its naturalistic methodology, and wide-ranging in the areas of philosophy it touches on. It explores a number of themes in the study of concepts, in the metaphysics of emergence, and in spacetime metaphysics. By doing so, it deepens our understanding of the relationship between three constants of everyday life: time, causation, and agency.