The approach, according to Inarritu, was to correspond to the smooth transition of nature from autumn to winter, and in addition, to help the actors to convey the evolution of the borderline mental state of their characters. However, weather conditions were unpredictable: where the authors expected to find autumn, they were met by snow storms with severe frosts, but when winter was needed, butterflies appeared everywhere and flowers bloomed. Because of this, the team had to fold the shooting several times and look for other locations.