Drifter Clint Barkley is riding through Utah's back country when he sees a group of cowboys chasing after a herd of wild horses, which is being led led by a magnificent black stallion whom he names Smoky. The cowboys catch some of the horses but give up the chase for the stallion. Clint goes after Smoky by himself, then appears a short time later at the Rocking R Ranch, which is run by Julie Richards and her grandmother, with the horse. After the cowhands help him herd Smoky into captivity, Clint asks Julie for a job as a wrangler, and she assigns him to break in some of the wild horses. Clint tries to break in Smoky gently, on his own time, and tells Julie that she should keep Smoky as a cow horse. Jeff, Julie's foreman who expressed doubts about hiring the stranger, and ranch hand Bill try to pry some information out of Clint about his past, but he is not forthcoming. Jeff tells Julie that he has heard a rumor in town that Clint was involved in a nasty scrape in Texas in which some money disappeared. One day when Julie goes to swim in a nearby river and encounters Clint working with Smoky, Julie tells him that she has known Smoky since he was only a few weeks old and has followed his development with interest and affection. She tells Clint about the rumor regarding his past, but he declines to explain himself. Soon after, a stranger named Frank comes to the Rocking R looking for Clint. Frank asks Clint, who took the blame for a crime Frank committed and has just completed an eight-month jail sentence, to get him a job on the ranch, and Clint reluctantly does. Later, Clint manages to get a saddle on Smoky and continues to train him as a cow horse. Bill thinks that Smoky will go back to the wild the first chance he gets, but the horse shows obvious affection for Clint. When Smoky chases Frank from the corral after he tries to move him, Jeff, who wants to sell Smoky, warns Clint that he will have to take the fight out of the horse or he will be turned loose. While the cowboys are out on a cattle drive, Smoky trips and Clint is thrown off and knocked temporarily unconscious. Smoky has an opportunity to leave but stays by Clint. Later, when Clint is unable to get up, he ties himself to Smoky's stirrup and has the horse drag him back to the ranch. While Clint is being nursed by Julie, Frank mistreats Smoky. After he is fully recovered, Clint is visited by a gambler who has an I.O.U. for $225, signed by someone using Clint's name. The gambler leaves after Clint tells him that he thinks he knows who signed his name and that he will try to get him the money. Clint extracts a confession from Frank and tells him to leave, but Frank threatens to tell Julie about Clint's past. After Clint socks him, however, Frank agrees to go. Clint and Julie, who are becoming romantically involved, are about to bring Smoky in from pasture when news arrives that he has been stolen along with several prime cattle. They suspect Frank, but Jeff insists that Clint might also be involved. This forces Clint to admit to Jeff and Julie that Frank is his brother and that he has always had to cover up for him and even went to jail for him. Frank, meanwhile, gets his payoff for the rustled cattle but holds on to Smoky. He continues to mistreat the horse, but stumbles and is killed by Smoky, who escapes. Clint sets out to track Smoky over many miles. Others have heard about the horse and succeed in capturing him, planning to use him in rodeos. Winter comes and Clint has to abandon his search temporarily and returns to the Rocking R. In the meantime, Smoky becomes "Cougar" the Bucking Bronco on the rodeo circuit, but is hurt and has to be retired. Clint keeps tracking Smoky and discovers that he has been given to a riding academy, but the owner has passed him on to someone whose name he can not recall. Sometime later in Cheyenne, Smoky is working as a junk cart horse when he sees a poster for a rival bucking bronco, hears the sounds of a rodeo parade and takes off to join the parade, junk cart and all. Clint is in the crowd, and while Smoky recognizes him and nudges him, Clint does not realize the horse might be Smoky until later. Clint tracks him to a junk yard and the weary, skinny old horse responds with heartfelt snorts and a whinny when Clint speaks his name. Back at the Rocking R, Smoky makes a speedy recovery, and Clint and Julie turn him loose in the pasture where the woods and canyons await him.
