This article gives an overview of the history of animated documentary, both in regard to the form itself and how it has been studied. It then goes on to present a new way of thinking about animated documentary, in terms of the way the animation functions in the texts by asking what the animation does that the live-action alternative could not. Three functions are suggested: mimetic substitution, non-mimetic substitution and evocation. The author suggests that, by thinking about animated documentary in this way, we can see how animation has broadened and deepened documentary's epistemological project by opening it up to subject matters that previously eluded live-action film.