This book is unique in the Christie canon by virtue of its distinctive setting – in a select girls' public school, Meadowbank. The claustrophobic atmosphere is well evoked and, amongst the staff, the formidable head teacher Miss Bulstrode is a particularly memorable character. Meadowbank attracts wealthy and eminent parents from home and overseas who seek the best education for their daughters and, as a result, the book offers a combination of whodunit and thriller, with the element of international intrigue handled better than in many of Dame Agatha's more sensational works.
When murder and mayhem come to Meadowbank, the school rapidly descends into chaos until an intelligent and sensible pupil called Julia Upjohn (Christie's skill at creating likeable young people has often been under-estimated) decides to call upon Hercule Poirot. It is rare for Poirot to enter the stage at such a late point in a Christie novel, but naturally his investigation uncovers the truth – although not until a further killing has occurred. This is a thoroughly enjoyable mystery.