Ralph Thomas directs Campbell's Kingdom, a screenplay adaptation by Robin Estridge from a Hammond Innes novel. The cast includes Dirk Bogarde, Stanley Baker, Michael Craig, Barbara Murray, James Robertson Justice, Athene Seyler, Robert Brown, John Laurie and Sid James. Clifton Parker composed the music, Ernest Steward handled cinematography. Bruce Campbell (Bogarde), facing a six-month life expectancy, travels to Come Lucky in the Rockies to claim his grandfather's legacy: Campbell’s Kingdom, a valley area where the elder Campbell maintained until his death that oil existed—a belief which created significant division within the town. Bruce finds himself unwelcome and learns that his inheritance will be challenged by plans for a dam; a project deemed ethically questionable but vital for local employment. Despite feeling vulnerable and isolated, he’s resolved to validate his grandfather's integrity and confronts Owen Morgan (Baker), who leads the dam construction effort. The filmmakers carefully develop the characters and their roles in the story. The film then gains momentum in its latter portion, delivering genuine excitement through a combination of underhanded tactics and action sequences. Ernest Steward’s Eastman Color photography is striking (Cortina d'Ampezzo in Italy substitutes for the Rockies), and the movie largely follows familiar Western themes involving opposing groups battling each other with inevitable suffering. The film contrasts Bogarde's refined presence against Baker's physical strength, both delivering strong performances. A supporting cast contributes to the character interactions, while the production design provides acceptable sets and miniature work when the story moves away from outdoor locations. Some aspects don’t entirely ring true, but the action and special effects are entertaining. A romantic subplot also helps move things forward, although it culminates in a somewhat frustrating ending. It's possible you might notice an absence of regional accents, or even question the morality on either side regarding the exploitation of the land. However, these minor points shouldn’t detract from the film’s overall enjoyment. It is a thoroughly agreeable piece of entertainment. 7.5/10

Source on TMDB