| CHAPTER | PAGE | |
| I | Lost | 9 |
| II | Fire! | 23 |
| III | Paul Looks Into the Matter | 28 |
| IV | Detectives | 36 |
| V | A Suspicious Individual | 44 |
| VI | The Spy | 53 |
| VII | The Robbery | 66 |
| VIII | Encounter | 73 |
| IX | Who Is Mr. Grey? | 81 |
| X | Stumped! | 90 |
| XI | A Hunch | 97 |
| XII | A Bump on the Head | 105 |
| XIII | Discovery | 113 |
| XIV | A New Turn of Events | 122 |
| XV | Following Up Their Clues | 131 |
| XVI | Paul Gets Into Trouble | 138 |
| XVII | Parental Admonitions | 149 |
| XVIII | False Alarm! | 156 |
| XIX | Captured! | 163 |
| XX | Escape! | 172 |
| XXI | Convincing the Police | 178 |
| XXII | Mr. Grey | 191 |
| XXIII | Paul Helps Out | 197 |
| XXIV | Battle | 204 |
| XXV | Into the Lake | 210 |
| XXVI | Trouble at Home | 218 |
| XXVII | Mystery of the White Card | 229 |
| XXVIII | Again the White Card | 237 |
| XXIX | Mystery Solved | 243 |