When Paladin finds a woman and her apparently typhoid-afflicted child abandoned by a wagonmaster, he enlists the aid of a female doctor from a nearby town, but a religious fanatic then tries to bar them from entry.

Dr. Phyllis Thackeray diagnoses the cook at the Barton Ranch with smallpox. All the cowhands may be infected and need to be vaccinated. Dr. Thackeray sends for the one man she thinks can help.