"Nurturing an implacable hatred against all of the house of Dhoon, that spirit, disembodied, would frequently be drawn to the neighbourhood of Mirza's descendants, both by hatred and by affinity. Two horrible desires of the Spirit Mirza would be gratified if a Dhoon could be made her victim--the desire for blood and the desire for vengeance! The fate of Lord Lashmore would be sealed if that spirit could secure incarnation!" Dr. Cairn paused, glancing at his son, who was writing at furious speed. Then-- "A magician more mighty and more evil than Mirza ever was or could be," he continued, "a master of the Black Art, expelled a woman's spirit from its throne and temporarily installed in its place the blood-lustful spirit of Mirza!" "My God, sir!" cried Robert Cairn, and threw down his pencil. "I begin to understand!" "Lady Lashmore," said Dr. Cairn, "since she was weak enough to consent to be present at a certain _seance_, has, from time to time, been _possessed_; she has been possessed by the spirit of a vampire! Obedient to the nameless cravings of that control, she has sought out Lord Lashmore, the last of the House of Dhoon. The horrible attack made, a mighty will which, throughout her temporary incarnation, has held her like a hound in leash, has dragged her from her prey, has forced her to remove, from the garments clothing her borrowed body, all traces of the deed, and has cast her out again to the pit of abomination where her headless trunk was thrown by the third Baron Lashmore! "Lady Lashmore's brain retains certain memories. They have been received at the moment when possession has taken place and at the moment when the control has been cast out again. They thus are memories of some secret cavern near Dhoon Castle, where that headless but deathless body lies, and memories of the poignant moment when the vampire has been dragged back, her 'thirst unslaked,' by the ruling Will." "Merciful God!" muttered Robert Cairn, "Merciful God, can such things be!" "They can be--they are! Two ways have occurred to me of dealing with the matter," continued Dr. Cairn quietly. "One is to find that cavern and to kill, in the occult sense, by means of a stake, the vampire who lies there; the other which, I confess, might only result in the permanent 'possession' of Lady Lashmore--is to get at the power which controls this disembodied spirit--kill Antony Ferrara!" Robert Cairn went to the sideboard, and poured out brandy with a shaking hand. "What's his object?" he whispered. Dr. Cairn shrugged his shoulders. "Lady Lashmore would be the wealthiest widow in society," he replied. "_He_ will know now," continued the younger man unsteadily, "that you are up against him. Have you--" "I have told Lord Lashmore to lock, at night, not only his outer door but also that of his dressing-room. For the rest--?" he dropped into an easy-chair,--"I cannot face the facts, I--" The telephone bell rang.