For a time the atmosphere was strained. Then Carroll recalled a particularly good college joke he knew and he told it well. After which Evelyn explained to Charley that Mr. Carroll was the wonderfulest piano player in the world and David Carroll, detective, strummed out several popular airs while the youngsters danced. Horrible as the situation was, it appealed irresistibly to his sense of humor. He found himself almost enjoying it. And he worked carefully. Eventually his patience was rewarded. He succeeded in getting them together on a lounge with a photograph album between them. And then, very quietly and positively, and with a brief--"Excuse me for a moment," he walked through the hall and into the living room. Lawrence and his wife were at opposite sides of the library table. At sight of Carroll, Lawrence laid down his paper and rose to his feet. "Well?" he inquired inhospitably. Carroll laughed lightly. "It got too much for me. Too much youth. I dropped in here for a chat with you folks." "I didn't understand that you had come to call on us," said Lawrence coldly. "Why, I didn't--" "You did!" snapped Lawrence. "I'm no fool, Carroll. From the minute I heard you were coming, I knew what you had up your sleeve. You wanted to talk about the Warren case! Now suppose you go ahead and talk--then get out!" CHAPTER XIII NO ALIBI Carroll was rarely thrown from a mental balance, but this was one of the exceptions to a rule of conduct where poise was essential. His eyes half-closed in their clash with the coldly antagonistic orbs of his host. His instinctive dislike of the man flamed into open anger and he controlled himself with an effort. One thing Lawrence had done: he had stripped from Carroll his disguise as a casual caller and settled down ominously to brass tacks. Carroll shrugged, forced a smile--then glanced at Naomi Lawrence. She had risen and was staring at her husband with wide-eyed indignation. Undoubtedly she was horrified at his brusqueness. For the first time, she, too, had made it plain that Carroll was not welcome--that his ruse of calling upon Evelyn had been seen through plainly--but he could see that even under those circumstances she was not forgetful that he was a guest in her home and, as such, he was entitled to ordinary courtesy. Carroll was more than a little sorry for her, and also a bit rueful at his own plight. Things had gone wrong for him from the commencement of the evening. And this--well, the gage of battle had been flung in his face and he was no man to refuse the challenge. But his muscles were taut until the soft voice of Naomi broke in on the pregnant stillness-- "Won't you be seated, Mr. Carroll?"