"Ah, yes. That requires thought."
Major Carstairs rubbed his hands together gaily, and Chloe burst out laughing.
"You two are nothing but schoolboys," she said joyously. "I believe you are both looking forward to this midnight adventure! You'd be quite disappointed if there were no need for your masterly plot after all!"
Anstice and Major Carstairs looked rather shamefacedly at one another; but Chloe was merciful and restrained further mockery for the time.
"Well, now I will make my suggestion," she said. "Leave the house in the usual way, by the front door; and come back, at whatever hour you agree upon, to the window here. I will let you in myself, and not a soul need know you have re-entered the house."
"Very well," Carstairs nodded. "One suggestion though. Leave the window open--no one will see behind those curtains, and go to bed as usual yourself. Depend upon it, if Tochatti is really the culprit, she will take all means of satisfying herself that you are safely in bed before she begins her work, and it would not do for her to find your room empty at midnight."
Chloe paled a little, and when she spoke her voice was uneasy.
"Leo, do you really think Tochatti is so--so malicious? I can't bear to think of her being with Cherry--she is with her almost night and day, you know--if she is so dreadful, so dangerous a character----"
"You need not be afraid, Mrs. Carstairs." It was Anstice who spoke, reassuringly. "The little one is quite safe with her, I am sure of that. If it really does turn out that Tochatti has been to blame, I feel convinced that we shall find she is not altogether responsible for her actions----"
"But that's worse still!" Chloe's voice was really alarmed. "If she is mad--a lunatic----"
"I did not mean quite that," said Anstice. "I meant--well, it is rather a difficult subject to enter into at a moment's notice; but--have you ever heard of a dual personality?"
"A dual personality?" She repeated the words, her white brow wrinkling with the effort of concentration. "I think I know what you mean--a person with two sides to his character, so to speak--of which first one is in the ascendant and then the other?"
"Kind of Jekyll and Hyde business, what?" Major Carstairs knew his Stevenson, and Anstice nodded.
"Well, something like that, though not so pronounced. There really are such people, you know--it is not only a fantastic tale that a man may lead a kind of double life, speaking in a spiritual and not a physical sense. You don't call such people lunatics, nor are they, save in extreme cases, criminals. But it is quite possible for a woman like Tochatti to devote one half of herself to your service--and serve you admirably!--and lead what seems in all respects an open and above-board existence; and yet, through some kink in her character, stoop to an action one would expect to find only in a woman of a thoroughly debased nature."