British crime film with a classic noir premise and location. A bankrupt tycoon (Rod Steiger) is chased from New York to Mexico by the law. By chance, he encounters another passenger on a train with a similar look. So he gets his unlucky double comatose on whisky and sleeping pills and dumps the body in the desert.
Of course, the ruthless businessman takes on the identity of his victim, but discovers that down in Mexico, this man is a rebel wanted for an assassination. So the impersonator steps into the shoes of an archetypal noir fall guy. Spain stands in effectively for the Tex-Mex border, mostly populated by British character actors
The first half of the film is a stylish thriller. As the fugitive leaves the train, he finds himself presented with the discarded man's dog which has been tied up in the luggage carriage. And this being an adaptation of Grahame Greene story, it becomes clear that dog moves in mysterious ways. It represents an interventionist god... and the border town is purgatory.
And the frontier bridge is the path to redemption! Burdened by all this symbolism, the later scenes aren't as as successful. But it is still an atmospheric journey through Greene's catholic subtext. Steiger leads effectively in a role which dominates. But the film is ultimately stolen by the dog, which gives one of the great canine performances!