In this paper, I outline a toy argument for metaphysical fatalism – i.e. there is no sense in which the world could have been different than it is. First, I explain a couple of assumptions that I make about the nature of time. These assumptions appear to be plausible and widely held – or, at least, they are reasonable positions to hold. Second, I outline and explain a thought experiment designed to bring our fatalist-friendly intuitions to the forefront.