Fort Scott offers a reward for Manuel Garcia, a Mexican bandit, who kidnaps Amby and asks for a ransom equal to the price Fort Scott is offering for his capture.
The shifting Rio Grande around an island leaves ambiguity as to what nation - The US or Mexico - has authority. The lawless take advantage and stay there.
Cord is assigned to accompany Jed Spangler who has just been released from Yuma prison. The authorities hope Jed will try to recover the loot he stole during the Civil War. Cord wants payback for a friend Jed killed.