Betty shot a swift glance at Trenholm and her figure grew rigid. "It is not a matter of like or dislike," replied Trenholm quietly. "It's a question of finding Paul's murderer. You asked me for a theory--and mine is a reasonable hypothesis." "Just a moment," broke in Roberts. "Paul was no slight weight. I doubt if Miss Ward could have lifted him in and out of bed unassisted, especially putting him back in bed--a dead body is an unwieldy object." "She could have killed him in bed," replied Trenholm. "But the other night you pointed out to Miss Ward and me that the lack of bloodstains on the sheets proved the crime was not committed in the bed," objected Alan heatedly. Trenholm eyed him thoughtfully. "You forget Miss Ward is a nurse," he pointed out slowly. "It would be a simple matter for her to change the bed linen with the dead man lying in it." Betty leaned forward in her earnestness. "And what became of the bloodstained sheets?" she asked. Trenholm uncrossed his long legs and leaned closer to her chair. "Ask Corbin," he suggested. Betty's grasp of her walking stick tightened, and she grew conscious of the atmosphere of the overheated room. Turning from Trenholm's direct gaze she saw Alan fumbling with his collar, his face a pasty white, and she seized her opportunity to divert attention from herself. "Are you ill, Alan?" she asked, her eyes big with concern. "Doctor, can't we have some fresh air in the room?" Roberts threw up the window nearest to him, then went to Alan's aid. Alan took the flask Trenholm proffered and drank eagerly, putting it down almost empty. "I'm better," he announced. "The room's infernally hot. Say, Guy," turning impulsively to him, "your theory's no good. What possible motive could Miss Ward have had to kill Paul?" "Frankly, I don't know"--there was something disarming about Trenholm's smile and Alan's anger cooled. "Miss Carter asked for a theory and I gave her one." Betty shrugged her shoulders. "Which won't hold water." Her voice altered and her companions gathered a hint of pent-up passion as she added, in tones which she strove to steady, "Paul's murder was no motiveless crime." "Quite so," agreed Trenholm. "And that motive was what, Miss Carter?" He waited in vain for an answer, and finally broke the pause. "Paul apparently had no enemies, and yet he was killed," he said. "Come, Roberts, you've known and loved the boy for years; you, Alan, were his first cousin and chum; Miss Carter, his," he paused, and she looked at him dumbly, "his one love. Among you, can you not tell the motive which inspired Paul's murder--was it hate, was it revenge, was it greed?" His deep voice lingered on the last word, then ceased. Roberts had touched him on the arm. At a sign from the physician Trenholm, without moving, turned his head and glanced at the open window. The light from one of the lamps shone directly on the outer blind. It had been turned a crack and in it peered a human eye.