Great actors in the midst of new technology. The plot is average. The main reason is that it was the movie studio's (Fox) first use of cinemascope. The land is the real protagonist of the film. The musical score is up and center in the film and it rides with the land. (The composer Bernard Hermann worked on Citizen Kane and a many Alfred Hitchcock films)
It takes place in Mexico through open and uninhabited territory. This choice of land allowed it to make use of the widescreen shot that surrounded the moviegoer to make him feel like he was really in the screen. There are great dialogue lines uttered by Richard Widmark. I can't fault the acting, it's just that the film was meant as a tribute to the landscape more than a story. There are great subtexts throughout, but they do not really come out or are a part of the narrative. It is an enjoyable film despite its limitations.
Cooper and Widmark arrive at a small town in Mexico when their ship has to dock for unexpected repairs. Hayward walks into the cantina where Cooper and Widmark settle in to ask for help to save her trapped husband at a gold mine. She will repay the help handsomely. No one wants to go there because it is a cursed land but four men take Hayward up on her offer. The rest of the film slowly proceeds as they make their journey through the rough terrain to the place where gold is abundant, but so is death: the Garden of Evil. On their trip back the group has to try to escape from the natives of the land to survive.
It left me with a big question on the use of the natives. Their presence and motivations seemed superficial; so I question the historicity and probability of the second act of the film. Again, it just seemed like the narrative was at the mercy of the land and so much of it might comes across as contrived. Despite that, it is an entertaining film for fans of the genre.