"My dear fellow, I've told you briefly my own theory—a theory formed upon all the evidence I could collect," replied the tall, dark-eyed man, as he thrust his hands deeply into his trousers pockets and looked straight into the eyes of his friend.

"If you are so certain that Enid Orlebar is implicated in the affair, if not the actual assassin, why don't you interrogate her?" asked Walter boldly.

"Well—well, to tell the truth, our inquiries are not yet complete. When they are, we may be in a better position—we probably shall be—to put to her certain pointed questions. But," he added quickly, "perhaps I ought not to say this, for I know she is a friend of yours."

"What you tell me is in confidence, as always, Trendall," he replied quickly. "I knew long ago that Enid was deeply attached to Bellairs. But much that you have just told me is entirely fresh to me. I must find Barker and question him."

"I don't think I'd do that. Wait until we have completed our inquiries," urged the other. "If Bellairs was killed in so secret and scientific a manner that no trace was left, he was killed with a cunning and craftiness which betrays a jealous woman rather than a man. Besides, there are other facts we have gathered which go further to prove that Enid Orlebar is the actual culprit."

"What are they? Tell me, Trendall."

"No, my dear chap; you are the lady's friend—it is really unfair to ask me," he protested. "Where the usual mysteries are concerned, I'm always open and above-board with you. But in private investigations like this you must allow me to retain certain knowledge to myself."

"But I beg of you to tell me everything," demanded the other. "I have taken an intense interest in the matter, as you have, even though my motive has been of an entirely different character."

"You have no suspicion that Bellairs was in possession of any great secret—a secret which it was to Miss Orlebar's advantage should be kept?"

"No," was the novelist's prompt response. "But I can't see the drift of your question," he added.