John Drum (Rod Cameron) appears to gun down the town sheriff in cold blood, but it turns out to be part of an elaborate ruse to allow Drum, a U.S. Army soldier, to infiltrate a gang of horse thieves. As Drum becomes more friendly with the gang, he also becomes more intimate with their women, Lin Connor (Ilona Massey) and Julie Ann McCabe (Adrian Booth). Drum's allegiances become strained as he bonds even more thoroughly with the criminals as they fight together against bands of Sioux warriors.