Tension is high in Wyoming cattle country due to low market prices for cattle, which have difficulty surviving the tough northern weather. Steve Patrick, who dreams of being the area's "Cattle King," strikes businessman Graycoe after he derides Steve for selling his herd at the bottom of the market. Planning to reinvigorate his herd, Steve borrows $6,000 against his mortgage from banker McCollum. After paying back wages to his friend and foreman, Bob Andrews, Steve reveals his plan to cross-breed Texas Longhorns with Hereford dairy cattle he intends to buy in Oregon. Steve believes the crossbred animal will be sturdy enough to survive the winters. Once he is successful, Steve plans to help re-stock his neighbors' ranches. Unknown to Steve, Bob forms a partnership with Graycoe and his associate, saloon owner George Maddox, to buy out the struggling local ranchers, and steal Steve's new herd for their own gain. Soon after, Bob and Steve leave for Oregon, but Bob is wounded when they exchange gunfire with two Indians who steal their horses. One of the Indians is killed, and Steve seeks help on foot. He encounters Janet Hale, a widow who lives with her son Chuck in a cabin nearby. Janet arranges for a doctor to treat Bob at her cabin, and allows him to convalesce there for several weeks. Janet grows fond of Steve, and loans him a horse and food to continue to Oregon. Steve arrives in Pendleton and buys 1,000 head of cattle from rancher Reed. However, when he attempts to hire a trail crew, he meets with resistance from the Cattlemen's Association, because it is off-season and the weather will be harsh. Steve encounters the same reluctance at a saloon frequented by cowpunchers, then proceeds to McClary's, a disreputable bar filled with rustlers and ex-convicts. There Steve is challenged to a fight by former outlaw Lynch, but after Steve fells him, Lynch is willing to talk business. Lynch and his friends sign up after Steve assures the distrustful group that they will receive regular wages and a job at his ranch if the herd survives the trip. In the meantime, Bob has recovered from his injuries and has fallen in love with Janet, who gently rejects his advances. Steve returns to the cabin, and although he is opposed to women and children joining a cattle drive, he hires Janet as his trail cook because she is in desperate need of money. Lynch becomes protective of the young Chuck, but Bob is irritable along the trail and suspicious of the crew, despite Steve's assurances that they are trustworthy and resilient. The weather turns cold as the cattle drive moves north, and they run low on food, with at least another week to travel. Steve and Janet fall in love, and Bob overhears when she accepts Steve's marriage proposal. One evening, Bob slips away to Maddox's camp nearby, and they plot to stampede the herd while Bob is on night watch. Although Bob now plans to kill Steve, he insists that Janet and Chuck be left unharmed. The next morning, Steve fires a trail hand, Kincaid, for drunkenness. Bob shoots Kincaid when he aims his gun at Steve, and after the wounded cowhand rides away, Bob tells Steve that his debt is paid. Later on, a troubled Bob learns that Lynch is loyal to Steve, and is surprised when the former outlaw suggests that Steve will share his success with Bob. That evening, the starving trail crew threatens to quit, but Steve surprises them with venison for dinner, thereby restoring the crew's faith and good humor. Steve later thanks Bob for his help and assures him that he expects Bob to have a ranch of his own if the breeding plans work out. A remorseful Bob attempts to call off his deal with Maddox, but is prevented from seeing him by Graycoe. When Bob draws his weapon, Graycoe struggles with him and is killed. The gunshot causes the herd to stampede, and Steve is awakened by the noise. He plans to guide the frightened herd into the canyon, but Bob warns him that it is a trap. Bob then turns on the rustlers and fires at them, causing Maddox to order both Bob and Steve murdered. Maddox ruthlessly shoots Bob, and is killed in revenge by Steve. After the stampede is quelled, Janet comforts the mortally wounded Bob, who confesses and apologizes to Steve before he dies. In time, Steve and his new family arrive at his ranch and, with great plans for the future of Wyoming, he promises to keep the first cross-bred cow as a pet.
