The Life and Legend of Wyatt Earp

Plague Carrier (4x13)

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Wyatt meets Dr. Carl McDowell and invites him to set up shop in Dodge City. However, Wyatt soon discovers that Carl doesn't have a license to practice. The town's current physician, Dr. McCarty, argues that experience is what counts. However, when a smallpox epidemic breaks out, they may both have to reconsider.