Ashton Kirk is a young man of high social position and great wealth; he is a deep student and learned in the lore of ancient tablets and forgotten books. His keen mind delights in those mysteries which have proven too shadowy for the police. He finds a joy in the hunt; there is a thrill in matching his intelligence against the craft of the criminal. His interest in the mystery of the house of fear, Cramp's house, was awakened by Pendleton, who, as a guest of Cramp, communicated to Kirk, his friend, the strange sense of mystery and fear surrounding Cramp's house. In Cramp's household lives Grace, his sister, Miss Hohenlo, his aunt, and Kretz, his servant. Kirk learns through his agent in Mexico that Cramp's father was an expert engraver in Mexico years before, and his astute mind connects this fact with the number of Mexicans in the vicinity. He also learns that, in a time of financial stress, Cramp's father forged some currency plates for one Alva, an unscrupulous Mexican, but at the last moment failed to deliver them. At the time of Kirk's visit, the plates rested securely under a great stone in the cellar of Cramp's house, and the presence of the prowling, murderous Mexicans, headed by Alva, was explained by this. The perplexing question, however, was how these intriguers managed to gain nightly entrance to the cellar in their search for the plates. It takes Ashton Kirk to resolve the queer markings on the string of a package sent to Miss Hohenlo into the message "tonight." That night, Kirk and his aides wait in the cellar as the unsuspecting Miss Hohenlo lets in her confederates. There is a big scene in which Alva and his men are overpowered, and it is learned that Miss Hohenlo is Alva's wife. Thus does Ashton Kirk solve the mystery of The House of Fear.