A compelling medical and scientific thriller by Robin Cook. The novel follows Dr. Edward Armstrong, a researcher involved in the development of new psychiatric medications. While studying a centuries-old Puritan settlement in Massachusetts, he uncovers a shocking connection between modern pharmaceutical research and a dark chapter of American history.

As Edward investigates, he discovers that a powerful drug company is testing an experimental mind-altering substance derived from a naturally occurring fungus. The drug appears capable of dramatically enhancing intelligence and creativity—but at a terrifying psychological cost.

The deeper Edward digs, the more he uncovers about unethical experimentation, corporate greed, and the dangers of manipulating the human mind. Soon, he finds himself caught between scientific ambition and a conspiracy that threatens both his career and his life.

Blending medical science, history, psychology, and suspense, Acceptable Risk is one of Robin Cook's most thought-provoking novels.