Agatha Christie’s detailed plotting is what makes her books so compelling. Christie used poison to kill her characters more often than any other murder method, with the poison itself being a central part of the novel, and her choice of deadly substances was far from random; the chemical and physiological characteristics of each poison provide vital clues to discovery of the murderer. With gunshots or stabbings the cause of death is obvious, but not so with poisons. How is it that some compounds prove so deadly, and in such tiny amounts?

Review
...a cracking compendium of Christie's poisonings...A Is For Arsenic will appeal to any fan of Christie's work, but as a potted history of poisons, antidotes and medicines it has much wider reach than that. -- Mark Lorch BBC Focus (Science and Technology) ...this book is fascinating and anyone who is interested in the myriad painful and unpleasant ways in which people can be killed will relish it. The Times

Kathryn Harkup is a chemist and author. Kathryn completed a doctorate on her favourite chemicals, phosphines, and went on to further postdoctoral research before realising that talking, writing and demonstrating science appealed a bit more than hours slaving over a hot fume-hood. For six years she ran the outreach in engineering, computing, physics and maths at the University of Surrey, which involved writing talks on science topics that would appeal to bored teenagers (anything disgusting or dangerous was usually the most popular). Kathryn is now a freelance science communicator delivering talks and workshops on the quirky side of science.