John Wayne -- showing off a darker side to his screen persona than we'd previously seen -- portrays Thomas Dunson, a frontiersman who, with his longtime partner Nadine Groot (Walter Brennan), abandons a westbound wagon train in 1851 to make his future as a rancher in Texas. Doing so forces him to abandon Fen (Colleen Gray), his fiancee -- and when she is killed in an Indian raid a short time later, it taints any good that Dunson might find in the future he carves out for himself, destroying any joy he might derive from life. The sole survivor of the raid is Matthew Garth (Mickey Kuhn), a young orphan who is unusually handy with a gun for one his age -- and already knows how to channel his grief and horror at what he's seen, as much as Dunson does. Dunson informally adopts Matt as his son, and over the next 14 years he builds up one of the largest ranches in the entire state of Texas. And all of it is worth nothing, a result of the economic ruin wrought on the state in the aftermath of the Civil War. Matthew (Montgomery Clift), now back from the war and doing some of his own adventuring, finds a darker, more taciturn Dunson than he's ever known -- as Groot tells it, he's afraid because he just doesn't know how to fight the threats he now faces. With Matthew now returned, Dunson decides to move his herd, nearly 10,000 head of cattle, to Missouri, where there is a market for beef, over 1000 miles away through territory controlled by border gangs hundreds of men strong that have stopped every cattle drive up to now, and Indians who have picked off what the gangs missed. Dunson drives his men as hard as he does himself, relentlessly, till even some of his best hands break under the strain -- and he's not above killing anyone who challenges his authority on the drive. He's able to hold them in line as long as Matthew backs him up, and he does until Dunson, exhausted and worn down by lack of sleep, finally goes too far. Matthew steps in, backed by laconic, smirking gunman Cherry Valance (John Ireland) and most of the rest of the men and takes the herd from Dunson. Leaving his father and mentor behind, he heads the herd toward Kansas, where -- so the men are told -- there's a new railroad. Along the way, he meets Tess Millay (Joanne Dru), a card-dealer who falls in love with the young man. But he has to finish the drive and leaves her behind, much as Dunson left Fen. And they all know that Dunson is coming after Matthew to kill him.