The film really comes down to just a couple of highlights: Tommy Tedesco’s beautiful guitar work on Jerry Goldsmith's theme music, and Jack Elam being ideally suited for the role of the grumpy, whisky-drinking "Mr. Phillips." Beyond that, it feels like a standard movie for John Wayne and Howard Hawks, with Wayne essentially carrying the entire picture. Jorge Rivero, Jennifer O’Neill, and Christopher Mitchum are just filling space. The plot is enjoyable enough – a Union colonel reconnects following the Civil War with two former Confederate officers to pursue someone who was leaking information during the war, leading to some fairly standard adventures before reaching an explosive ending.

Source on TMDB