Jess Remsberg (James Garner) is a man on a mission of revenge. His wife, a Comanche woman, has been killed. Jess suspects that the unknown murderer is one of Leiutenant Scotty McAllister’s (Bill Travers) men, but he doesn’t know exactly who.

While crossing the harsh terrain of the old West, Jess comes across Ellen Grange (Bibi Andersson), whose horse has died. Ellen herself is in pretty bad shape, too, after traveling the land alone with virtually no supplies. Jess decides to take her back to Fort Creel, where her husband (Dennis Weaver) lives.
When Ellen returns to Fort Creel to find that her husband wants nothing to do with her, she decides to leave town, but she’ll soon discover that the Apache she used to live with aren’t too happy with her either.
Meanwhile, Mr. Grange, Leiutenant McAllister, horse-breaker Toller (Sidney Poitier), and McAllister’s cavalrymen also leave Fort Creel in attempt to transport a wagon load of ammunition and other goods through hostile territory.
Duel at Diablo was directed by Ralph Nelson, who also directed Sidney Poitier in Lillies of the Field. The film is based on a novel by Marvin H. Albert, who also co-wrote the script along with Michael M. Grilikhes.
I’ve come to enjoy Westerns, but not all of them are free of the problems that once led me to disregard the entire genre. Duel at Diablo is a great example of a film that’s highly entertaining, and that I may even consider a new favorite… if not for a few unavoidable issues.
My biggest problem with Duel at Diablo is the fact that its cast includes only one credited Native American actor, Lakota actor Eddie Little Sky. The main Apache character, Chata, is played by John friggin’ Hoyt of Attack of the Puppet People fame, dolled up in a synthetic dollar store “Indian” wig. The Apache are given some chance to explain their motivations, which I did appreciate, but I still thought the film demonized them and treated them as evil “savages.”
Despite its very typically mid-century, messy handling of its Apache characters, there are many things the film does well. When it comes to other serious issues, the film offers much more thoughtful commentary. The unfair treatment of Ellen due to her involvement with an Apache man, for example, is harshly portrayed, reflecting negatively not on Ellen but on those who judge her.
Ellen explicitly tells Jess that she’s disgusted by the double standard — she is shunned for having a relationship with an Apache man, while he married a Comanche woman and faced no consequence. As Jess points out, this isn’t totally true, as he has suffered by losing his wife. But at least he still has his life. Ellen and Jess’ wife each take the blame for these relationships, and face much harsher consequences than the men they love, something the film does not shy away from.
Sidney Poitier’s portrayal of Toller adds another interesting element to the film in that his race is not a point of contention between himself and the other characters. One may expect, the film being released in the ’60s and set in the 1800s, that Toller’s race would play at least some part in the story. Instead, he’s generally a respected man, a horse breaker and former soldier who only finds himself at odds with the others when they disagree on how to deal with the situation at hand.

I especially enjoyed the scenes Poitier shares with James Garner. Both men give great performances.
Duel at Diablo also has a well-established, grim tone and high tension. The music is great, and the film is nicely shot, beautifully filmed on-location in Utah. From a technical standpoint, it’s a well-constructed piece of work, with plenty of action (some of which gets pretty gruesome!).
I would recommend giving Duel at Diablo a watch, despite my issues with its treatment of its Apache characters. It’s a tense, nicely-made Western with top-notch performances from its leads.