The case is not that interesting (or pedestrian in Agatha Christie's standard): a woman suddenly died while sitting in a cave entrance. The woman is a sadist and loves to torment her family so naturally suspicions hover above the family members' heads. And since this is an Agatha Christie novel, the most suspicious ones, those with the highest chance of perpetrating the killing, are always absolved and the least likely ones end up as the culprit.

This is the first Christie novel where I guessed the culprit early on. When the killer was revealed, I was as ecstatic as when I guessed a House episode's diagnosis before Dr. House did! This novel also presented a moral dilemma: is the killing of an evil person ever be justified? That question left my mind in tenterhooks with endless pros and cons volleying to and fro.

Summing this review up (and because I babbled more than I meant), Agatha Christie is a terrific writer with so many plot twists to spare. This novel is not her best but her ingenuity is on full display.