“So you see,” he concluded, “that woman must have been in the library some time after dinner. Now who was it? Barbara was with you in the garden, of course; so she’s out of the running. That leaves Mrs. Shannon, Mrs. Plant, and Lady Stanworth—if it _was_ somebody in the house, by the way,” he added thoughtfully. “I never thought of that.” Alec paused in the act of tying his black tie to look round interrogatively. “But what’s all this getting at?” he asked. “Is there any particular reason why one of those three shouldn’t have been in the library yesterday evening?” “No, not exactly. But it rather depends on who it is. If it was Lady Stanworth, for instance, I shouldn’t say there was anything in it; unless she specifically denied that she went into the library at all. On the other hand, if it was someone from outside the household it might be decidedly important. Oh, it’s too vague to explain, but what I feel is that this is the emergence of a new fact—the presence of a woman in the library yesterday evening. And a woman sitting down at that, not just passing through. Therefore, like every other fact in the case, it has got to be investigated. It may turn out to be absolutely in order. On the other hand, it may not. That’s all.” “It’s certainly vague, as you say,” Alec commented, fastening his waistcoat. “And when do you expect to spot the woman?” “Possibly the end of dinner. I shall sniff delicately and unobtrusively at Lady Stanworth and Mrs. Plant, and if it isn’t either of them, it may be Mrs. Shannon. If that’s the case, of course there’s no importance to be attached to it at all; but if it isn’t any of them, I don’t know what I shall do. I can’t go dashing all over the county, sniffing at strange women, can I? It might lead to all sorts of awkward complications. Hurry up, Alexander, the bell went at least five minutes ago.” “I’m ready,” Alec said, glancing at his well-flattened hair in the mirror with approval. “Lead on.” The others were already waiting for them when they arrived in the drawing room, and the party went in to dinner at once. Lady Stanworth was present, to all appearances unmoved, but even more silent than usual; and her presence laid an added constraint on the little gathering. Roger tried hard to keep the ball rolling, and both Mrs. Plant and Jefferson did their best in their respective ways to second him, but Alec for some reason was almost as quiet as his hostess. Glancing now and again at his preoccupied face, Roger concluded that the rôle of amateur detective was proving highly uncongenial to that uncompromisingly straightforward young man. Probably the introduction of this new feminine question regarding the ownership of the handkerchief was upsetting him again.