In the canonical literature (Huizinga, Caillois), play has been thought in its rapport with culture. This rapport is often described as paradoxical, as being organized around the two opposite if not incompatible poles of rule (order, discipline) and fiction (creative liberty and fantasy), corresponding roughly to the significations of the words game and play in English. Based on long-winded ethnographic research, this article focuses on an under-studied phenomenon: live action role-playing games (LARP). As a sort of immersive and ludic voyage in fictional worlds, participants in LARP’s play out costumed characters according to precise rules of simulation, yet with the opportunity to come and go as they please and to make their own choices. Reconciling game and play, LARP’s are original forms of cultural creation which are not only collective but collaborative.