Cico is attacked by a young Fox, little more than a teenager. Zagor stops him and takes him back to his camp, where the tribal chief apologizes and offers him a sumptuous dinner.
However, Zagor hears moans from a hut, and understands that the Foxes have something to hide: he therefore leaves the camp. He returns at night and manages to free the prisoner: it is Doctor Jim Galloway, kidnapped by the Foxes to treat a typhus epidemic.
Pursued by the Foxes, the three take refuge at the top of a hill, where Zagor puts up a strenuous resistance. The doctor, however, realizes that he wants to help the Indian tribes voluntarily, and therefore stays with them, putting an end to the fight.
On the way to the cabin, Zagor and Chico come across the abandoned carriage of "Bimbo" Sullivan , a merchant that Zagor knows.
Tracking him down thanks to his tracks, Zagor saves him from two Indians, but "Bimbo" runs away without almost saying goodbye to them, forgetting to take his hat. Zagor and Chico continue along the road, and stop at a hut, where they sleep. When he wakes up, Chico is wearing "Bimbo's" hat. However, two criminals arrive who, thinking that Chico is "Bimbo" Sullivan, want to sell him some contraband goods. Zagor intervenes, and in the fight he defeats them and sends them to prison.
