It was a long journey that no one had tried before. Jeff Kennett and his drovers have brought a herd of 2,000 longhorns from Texas to California through a northern route that has taken them two years to complete. The Gold Rush is on and there is a tremendous demand for beef and no way to get it. Kennett believes he can make a fortune by transporting the cattle by riverboat from Lassen Meadows down the Sacramento River for sale in San Francisco. He has been referred to Captain Bill Ballinger, headquartered in Sacramento, as the man who can best pilot the cattle downriver, transporting the herd in increments aboard The Sunset Trail. At a U.S. Army camp on the Truckee River, Kennett first met Deborah Sharpe, who was traveling from Boston to join her father in Sacramento. Kennett renews their acquaintance when he is invited to the home of her father, Colonel Nathaniel Sharpe. The colonel, with his partner, Noah Carlin, is in the shipping business with a fleet of riverboats and assures Kennett that they can transport the cattle faster and at less expense than Ballinger. When Kennett turns them down, Noah Carlin threatens that Kennett will never get his cattle to San Francisco. It is soon clear that Sharpe and Carlin will do everything they can not only to stop The Sunset Trail from transporting Kennett's cattle, but to seize the herd for themselves.