‘On the day before the shoot, I wandered around the fairly run down outpost of Forsyth, Eastern Montana, trying to find another layer to the story. When I went to buy a drink, I found that I had run out of dollars, so I nipped across the street to the ATM. As my dollars came out, I had one of my rare moments of inspiration. We should use flying dollars in the photograph. My new narrative was that the car passengers stumbled across a frozen cash treasure trove - as seemingly happens regularly in this part of the world’.