Two fascinating novels by Nayo Marsh about the adventures of the Scotland Yard inspector, the intellectual policeman Roderick Alleyn, are classic detective stories full of subtle, purely British humor. A group of relatives, friends and acquaintances of an eccentric millionaire decides to while away the evening in a country house with a fashionable “game of murder". However, the game ceases to be a game when one of the guests is found stabbed to death with a dagger. Who got rid of the respectable Sir Charles? Everything is under suspicion, from the victim's lively cousin - a gossip reporter - to the Russian emigrant butler. And each suspect, Alleyn finds out, had both motives and opportunities. In the absence of her husband, who is away on a business trip, Alleyn’s wife, a talented artist Troy, goes on a small boat on a pleasure cruise along the Thames. The atmosphere on the ship is cozy, despite the motley, varied company of passengers. But something seems subtly suspicious to Troy, something makes her tensely wait for events. And her expectations are justified when someone brutally kills an annoying, funny, but good-natured old maid. Troy decides to start his own investigation...