As he is on his way to trial, Sinclair tells about his wife and how sick she was. He explains he killed her out of mercy because she was in a lot of pain. But when he found out she'd given all her money to her mother and sister he found he had to kill them too. He also mentions a twin brother, who he seems to blame for his bad luck in America.
After being captured, Sinclair and six other prisoners ride the tumbleweed wagon of Marshal Wilt Jackson and Deputy Art Gray to get to Fort Gregg, where their trial awaits. Sinclair gets to like Virgo, an Indian who doesn't speak his language and therefore doesn't talk back.
When the prisoners try to escape and only one of them succeeds, the Deputy gets killed and the sheriff is badly injured. Trail boss Gil Favor and Rowdy Yates, his ramrod, take over and set out to take the prisoners to the Fort.
Along the way, as they're sitting around the camp fire, fellow prisoner Dallas takes a piece of wood out of the fire and throws it in the bushes to distract the two cattlemen. As they are busy putting out the fire, Dallas and Sinclair run up a hillside. There Sinclair strangles her and tries to kill her but Norm Morton, another prisoner, saves her just in time.
After the escaped prisoner gets help from Dallas's husband Luke Storm and his gang, the two cattlemen try to outrun the men by getting the wagon to the other side of a river. The prisoners are all on top of the wagon as they come to a stop when Favor and Dallas get pushed into the water. As the two get out of the river, Storm is waiting to kill Favor. Dallas, however, is more angry at Sinclair for almost killing her and aks her husband to kill him instead. Without any doubt he turns to Sinclair, who's standing on top of the wagon, and shoots him, hereby killing him and making him fall into the river.