In this expose, Allen M. Hornblum tells the story of Philadelphia's Holmesburg Prison. From the early 1950s through the mid-1970s, Holmesburg's inmates were used, in exchange for a few dollars, as guinea pigs in a host of medical experiments.

Based on in-depth interviews with dozens of prisoners as well as the doctors and prison officials who, respectively, performed and permitted these experimental tests, Hornblum paints a disturbing portrait of abuse, moral indifference, and greed. Central to this account are the millions of dollars many of America's leading drug and consumer goods companies made available for the eager doctors seeking fame and fortune through their medical experiments.

Many of these doctors established their illustrious careers on the backs of the inmates who served as the ideal test subjects - isolated, cheap, and locked behind bars.