Led by Dr. Leo L. Stanley, the experiments include testicular implants and other "positive" eugenics-based testing focused on "revitalizing" youth in older white men. Stanley believes that white men's genes are "superior," and should therefore be preserved to uphold the "moral values" of the U.S.

Five hundred incarcerated men at San Quentin undergo testicular transplants, some of whom have the glands of rams, goats, and boars surgically implanted in their scrotums. If consent for the transplant is not given, Stanley coerces people to undergo the procedure by claiming it will increase their "sexual vigor."