Surely no customer could be seeking admittance at such an hour! Besides, the knocking was clamorous, insistent, not in the least like the furtive taps which usually proclaimed the visit of some client, anxious to hide his errand under the cover of darkness. With a shrug of his shoulders Mr. Ludgrove put down his cup and went to the door. He drew back the bolts and put out his head, to find Ted Copperdock standing on the pavement outside. The young man gave him no chance to ask questions. He threw out his hand and caught Mr. Ludgrove by the arm, as though to drag him forcibly into the street. “For God’s sake come and see Dad!” he exclaimed. “Why, what has happened?” enquired Mr. Ludgrove quickly. “I don’t know, he’s dead, I think,” replied Ted incoherently. “I’ve just come back and found him. Something terrible’s happened——” Mr. Ludgrove was not the man to be carried off his feet by a sudden crisis. “Certainly, Ted, I’ll come over,” he said quietly. “But you appear to want a doctor rather than me. You probably know that a detective has been patrolling the streets for the last few nights. I think I see him coming towards us now. You go and fetch the doctor, while he and I attend to your father.” Ted, after a moment’s hesitation, ran off down the road, and Mr. Ludgrove walked swiftly towards the advancing figure, which he had already recognized. “Something has happened to Mr. Copperdock,” he said as he reached him. “I have sent his son for a doctor, and said that you and I would go in.” “Something happened, eh?” replied the man, as the two strode swiftly towards the door of the tobacconist’s shop. “You don’t know what it is, I suppose? I’ve had my eye on the place all the evening, and there’s been nobody near it between eleven, when two fellows whom Copperdock took in came out, and five minutes ago, when his son let himself in with a key. And there’s been a light in the front window upstairs all that time.” “No, I know nothing,” replied Mr. Ludgrove anxiously. They had reached the shop by this time. The door had been left open by Ted in his haste to call the herbalist, and they hurried on through the shop and up the staircase to the first floor. The door of Mr. Copperdock’s bedroom stood open, and they rushed in together. On the threshold they halted, moved by a simultaneous impulse. Before them, in the middle of the floor, lay Mr. Copperdock, stripped to the waist, with an expression of innocent surprise upon his face. Chapter XII A Hypodermic Needle For a moment the two men stood still, rooted to the ground with horror. Then Mr. Ludgrove stepped forward and fell on his knees by Mr. Copperdock’s side. He put his finger on his wrist for a moment, then slowly rose to his feet and shook his head.