Dr Kathryn Harkup, a former chemist turned writer and science communicator, talks about how Agatha Christie revelled in the use of poison to kill off unfortunate victims in  her books; indeed, she employed it more than any other murder method, with the poison itself often being a central part of the novel. This talk looks at how the writer used her extensive knowledge of drugs and medicines mixed with real life cases to create her brilliantly plotted crime novels. Her poisons were picked with care, often providing vital clues to the discovery of the murderer. We will look at ‘howdunnit’ but whodunnit is for you to find out.