The far-off star Altair-IV, occupied by two lone inhabitants and Robby the Robot, is visited by a search party from Earth.

Any Johhny Reb who tries to escape the Union prison outpost at Fort Bravo faces the unforgiving Arizona Territory desert stretching out before him ... and the even more unforgiving pursuit of Bravo's resolute Captain Roper. Yet there's a common foe that may unite the Civil War rivals: the fierce Mescalero horsemen waging guerilla war against Blue and Gray alike.