“Reginald Foster!” replied her husband promptly. “The biggest bore in creation.” He began to shake again with unholy glee. “Have you any blood left, Doyle?” “Precious little, and I don’t mind telling you that I’m not parting with it. There may be a few scrapings in the cup, though. Why?” “Just an idea. Here, George; something you can do. On the hall-table you’ll see a cup, bearing traces of blood. Wipe that handkerchief round inside it, and then go and drop it on the river’s brim—where we’ll hope that not even the Inspector from Scotland Yard will mistake it for a primrose. Hurry, won’t you?” George hurried. “I think you’re being perfectly horrible, Guy,” said his wife. “Why couldn’t you go on using red-ink, like civilised human beings?” “Because red-ink when analysed does not respond to the tests for human blood, wife.” “But good gracious, you’re not expecting matters to get as far as that, are you?” “I was once a Boy Scout, Cynthia,” Mr. Doyle intervened, “and my motto was ‘Be Prepared.’ It still is. Another of my mottoes,” he added thoughtfully, “if I remember aright, was ‘Zing-a-zing, Bom Bom!’ But don’t ask me what that means, because I never could discover. It’s probably Jugo-Chzechovinian.” “But what did you _do_ with the blood?” Cynthia pursued. “Oh, just sprinkled it about in convenient dollops, like the gentle dew from Heaven, you know.” “Well, goodness knows what’s going to come of all this,” Cynthia sighed. “I say,” remarked George, with the appearance of careful thought, “wouldn’t it be a good idea to put your brother and sister off now? Er—supposed to be coming on Tuesday, aren’t they? Yes,” said George weightily, “if I were you I should put them off.” “We’re certainly going to get into the most dreadful mess,” said Cynthia, not, however, relieving George’s mind. “Your library carpet’s got into that already,” said Mr. Doyle consolingly. “Enough of this chatty badinage!” Dora broke in. “Do you know that Mr. Reginald Foster has gone galloping off for the police? He won’t find him, because he won’t think of looking in your library cupboard, but he’ll ring up the nearest station; and then things are going to get busy. We’ve got to work out a plan of campaign. Remember I’ve had it put on record that our host and hostess were lured away from the house.”