I find myself consistently having difficulty connecting with the performances of two actors in particular: Tom Hanks and Kevin Costner. The way he tells this story through his journal feels relentlessly even-toned, which diminishes what is otherwise a visually stunning narrative. He plays "Lt. Dunbar," who, after narrowly escaping Confederate forces during the American Civil War, is sent to a remote outpost where he lives alone with a wolf ("Two Socks"). That changes when another warrior spots him bathing and alerts their people. What follows is a slowly unfolding story about his evolving connection with the nearby Sioux tribe. The film benefits from a distinctive John Barry musical score and some impressive cinematography, and the performances of Graham Greene (“Kicking Bird”) and numerous other Native American actors are commendable. It’s really Costner's presence that holds it back; he was clearly influential in getting this production made, and while he shows directorial talent, his acting is just too dulling to watch. He fails to communicate the feelings of isolation, apprehension, and happiness that his character goes through as he gradually integrates into a new – at times harsh – way of life. The story highlights and reveals the common beliefs of both groups regarding each other, their uncertainties and lack of trust—and if someone with more acting gravitas had taken on the role of “Dunbar,” we might have ended up with a truly remarkable film instead of just a lengthy one. It’s still worthwhile to watch, but it would have been significantly better with a stronger performance from the lead.

Source on TMDB