One of my favourite films of all time, I love it because no one will reveal the truth about the ending. When it’s all said and done and the parasitic, shape-changing alien had laid waste to the entire arctic station, we’re left with two men – Macready and Childs.

As they share a bottle of whisky and wait for death, we don’t know which one of them is the alien. Some look to the fact that one of them doesn’t exhale any breath in the cold air, while others try to watch the film and track where the alien goes and when it could have replaced either men. The director isn’t talking, neither is Kurt Russel, leaving the ending up for debate and the audience unsettled.