He stopped short as a taxi-cab driven at a considerable speed, came rushing down the street and passing them swiftly turned into the wider road beyond. And the sudden exclamation was forced from his lips because it seemed to him that as the cab sped by he saw a yellow-hued face within it--for the fraction of a second. Quick as that glimpse was, Ayscough was still quicker as he glanced at the number on the back of the car--and memorized it. "Odd!" he muttered, "odd! Now, I could have sworn--" He broke off, and hurried after Mirandolet who had stridden ahead. "Here we are, doctor," he said, as they came to the door of the mortuary. "There's a man on night duty here, so there's no difficulty about getting in." There was a drawing of bolts, a turning of keys; the door opened, and a man looked out and seeing Ayscough and Dr. Mirandolet, admitted them into an ante-room and turned up the gas. "We want to see that Chinaman, George," said the detective. "Shan't keep you long." "There's a young foreign doctor just been to see him, Mr. Ayscough," said the man. "You'd pass his car down the street--he hasn't been gone three minutes. Young Japanese--brought your card with him." Ayscough turned on the man as if he had given him the most startling news in the world. "What?" he exclaimed, "Japanese? Brought my card?" "Showed me it as soon as he got here," answered the attendant, surprised at Ayscough's amazement. "Said you'd given it to him, so that he could call here and identify the body. So, of course, I let him go in." Ayscough opened his mouth in sheer amazement. But before he could get out a word, Mirandolet spoke, seizing the mortuary-keeper by the arm in his eagerness. "You let that man--a Japanese--see the dead Chinaman--_alone_?" he demanded. "Why, of course!" the attendant answered surlily. "He'd Mr. Ayscough's card, and--" Mirandolet dropped the man's arm and threw up his own long white hands. "Merciful Powers!" he vociferated. "He has stolen the diamond!" CHAPTER THIRTY-ONE THE MIRANDOLET THEORY The silence that followed on this extraordinary exclamation was suddenly broken: the mortuary keeper, who had been advancing towards a door at the side of the room, dropped a bunch of keys. The strange metallic sound of their falling roused Ayscough, who had started aside, and was staring, open-mouthed, at Mirandolet's waving hands. He caught the doctor by the arm. "What on earth do you mean?" he growled. "Speak man--what is it?" Mirandolet suddenly laughed. "What is it?" he exclaimed. "Precisely what I said, in plain language! That fellow has, of course, gone off with the diamond--worth eighty thousand pounds! Your card!--Oh, man, man, whatever have you been doing? Be quick!--who is this Japanese?--how came he by your card? Quick, I say!--if you want to be after him!"