After seven years of struggling to make ends meet and working hard and late in London hospitals, John Wolfe finds himself in the town of Navestock as an assistant to Dr. Threadgold. He is assigned to the poor districts of the town where he gets faced with an increase of illnesses caused by poor sanitation. He discovers that the town's water supply is polluted, causing dangerously unsanitary conditions in these districts. When he seeks reform in order to improve conditions, he comes against small town politics and greed of the town's officials who threaten to cause epidemic. Young doctor is decisive to make a difference and he meets a woman who gives him courage to face many tough challenges.