A cobra has been found in Precious Ramotswe's office. Then a nurse from a local medical clinic reveals to Mma Ramotswe that faulty blood-pressure readings are being recorded there. And it looks as though Aunty Emang, the advice columnist in the local newspaper, may not be what she seems. It all means a lot of work for Mma Ramotswe and her inestimable assistant, Grace Makutsi, and they are, of course, up to the challenge.