The virtual reality component lasts about seven minutes. In that part, the landscapes are photographs on which the actors stand, incorporated digitally. Advances in technology - and the fact that the sand is there under your feet - make the experience really transport you. When the dust rises when you take a step, you forget that the French Riviera is just outside. (The director of photography Emmanuel Lubezki, a frequent contributor to Iñárritu, is the one who took the detailed and threatening images of the exteriors used in the RV).