Sir Henry Merrivale is on horseback again. This time we will have to investigate a case in which the victim, at first glance, tried to rob himself, and as a result received a dagger in the chest. A lot of questions immediately arise - why, why and how. Of course, Sir Henry will present the main question, as well as the answer to it, at the very end. The peculiarity of this case is that, parallel to Merrivale, a police inspector, sent to the victim’s house incognito and for special purposes, came to the same conclusions, albeit through a slightly longer route.