I am often asked by readers where I get my ideas from. The internet is a wonderfully random way to get ideas, particularly local news and social media. For example, as I was beginning my last book I knew that it would be based at a posh boarding school and that there would be a school production of Hamlet. I was on twitter and offered my 1,000th follower the opportunity to be named in the book. A certain Jo Rhodes came along and it turned out she was an expert in medicinal plants – and poisonous ones. Suddenly I had a possible cause of death and a title taken from Hamlet: ‘Potent Poison’.