This photograph, taken high in the mountains of Montana, offers strong clues as to why Cara Delevingne is a global superstar. She has the eyes and the face to steal most scenes and the intelligence to play a prescribed role. There is nothing I would change in her look in this vignette. It is a perfect combination of purpose and rather unhinged menace. She can do this as easily as some people flick a switch.

Chief John Spotted Tail of the Lakota tribe was an excellent foil for Cara and they work well together. He is revered locally and it was an honour to have him on set. He brings a further edge to an image encapsulating my read on the old Wild West: a place of guns; trouble in hard drinking saloons; occasional bad weather and maverick characters. No wonder Westerns have a film genre to themselves - it is too rich a seam in the material to have to share a category with anything else. To go “West" was perhaps the greatest adventure story the world has ever known.