Supernatural detective Thomas Carnacki is on the case of a mysterious horse in this haunting short story by fantastic fiction writer William Hope Hodgson.

There is a legend in the Hisgins family: any first-born female will be haunted by a ghostly horse during her courtship. The story has long been dismissed as nonsense—until their daughter Mary's fiancé, Beaumont, is attacked by a mysterious assailant. Detective Thomas Carnacki is summoned to investigate.

Several strange incidences begin to occur during the detective's stay. Family members are woken by the sound of hoof beats in the night, yet no horse can be found nor any evidence of hoof prints on the grounds. A horrible neighing is heard in the cellar and Beaumont, injured again, is certain that he's glimpsed an enormous horse's head. The detective searches frantically for answers and the terrified family acts quickly to hasten the wedding—fearing the worst. In the midst of the chaos, surprising evidence comes to light, with strange and fatal results.