| CHAPTER I. THE MASTER OF HARKINGS |
| CHAPTER II. AT TWILIGHT |
| CHAPTER III. A DISCOVERY |
| CHAPTER IV. BETWEEN THE DESK AND THE WINDOW |
| CHAPTER V. IN WHICH BUDE LOOKS AT ROBIN GREVE |
| CHAPTER VI. THE LETTER |
| CHAPTER VII. VOICES IN THE LIBRARY |
| CHAPTER VIII. ROBIN GOES TO MARY |
| CHAPTER IX. MR. MANDERTON |
| CHAPTER X. A SMOKING CHIMNEY |
| CHAPTER XI. “... SPEED THE PARTING GUEST!” |
| CHAPTER XII. MR. MANDERTON IS NONPLUSSED |
| CHAPTER XIII. JEEKES |
| CHAPTER XIV. A SHEET OF BLUE PAPER |
| CHAPTER XV. SHADOWS |
| CHAPTER XVI. THE INTRUDER |
| CHAPTER XVII. A FRESH CLUE |
| CHAPTER XVIII. THE SILENT SHOT |
| CHAPTER XIX. MR. MANDERTON LAYS HIS CARDS ON THE TABLE |
| CHAPTER XX. THE CODE KING |
| CHAPTER XXI. A WORD WITH MR. JEEKES |
| CHAPTER XXII. THE MAN WITH THE YELLOW FACE |
| CHAPTER XXIII. TWO’S COMPANY ... |
| CHAPTER XXIV. THE METAMORPHOSIS OF MR. SCHULZ |
| CHAPTER XXV. THE READING OF THE RIDDLE |
| CHAPTER XXVI. THE FIGURE IN THE DOORWAY |
| CHAPTER XXVII. AN INTERRUPTION FROM BEYOND |
| CHAPTER XXVIII. THE DEATH OF HARTLEY PARRISH |