Used for war and suicide, medicine and cosmetics, poisons permeate our world, found in the environment as well as in our homes. Taking a lighthearted view of the subject, the author of Bittersweet: The Story of Sugar considers poisons in all their aspects, exploring the science and the sources—from cyanide to strychnine, from Botox to Sarin gas—as well as the means of their detection. Along with pondering whether Abraham Lincoln's mood swings were caused by mercury poisoning and whether Jack the Ripper ate arsenic, Peter Macinnes also discusses such historical figures as Nero, Socrates, and British portraitist Thomas Wainewright—who poisoned his sister-in-law for having "thick ankles"—while from literature, he cites Hamlet and Peter Pan.