| # | Title | Year | Chapters | Pages | |
|---|---|---|---|---|---|
| 1. | The Secret of Skeleton Island | 1949 | 19 | 214 |  |
| 2. | The Riddle of the Stone Elephant | 1949 | 22 | 213 |  |
| 3. | The Black Thumb Mystery | 1950 | 20 | 216 | |
| 4. | The Clue of the Marked Claw | 1950 | 21 | 211 | |
| 5. | The Clue of the Coiled Cobra | 1951 | 19 | 214 | |
| 6. | The Secret of Hangman's Inn | 1951 | 20 | 213 | |
| 7. | The Mystery of the Iron Box | 1952 | 20 | 214 | |
| 8. | The Clue of the Phantom Car | 1953 | 21 | 214 | |
| 9. | The Mystery of the Galloping Horse | 1954 | 20 | 212 | |
| 10. | The Mystery of the Green Flame | 1955 | 16 | 212 | |
| 11. | The Mystery of the Grinning Tiger | 1956 | 14 | 209 | |
| 12. | The Mystery of the Vanishing Magician | 1956 | 18 | 215 | |
| 13. | The Mystery of the Shattered Glass | 1958 | 11 | 184 | |
| 14. | The Mystery of the Invisible Enemy | 1959 | 14 | 182 | |
| 15. | The Mystery of Gallows Cliff | 1960 | 15 | 184 | |
| 16. | The Clue of the Silver Scorpion | 1961 | 10 | 180 | |
| 17. | The Mystery of the Plumed Serpent | 1962 | 16 | 176 | |
| 18. | The Mystery of the Sultan's Scimitar | 1963 | 15 | 177 |
| Title | Year | Chapters | Pages | |
|---|---|---|---|---|
| The Clue of the Marked Claw | ||||
| The Clue of the Coiled Cobra | ||||
| The Secret of Hangman's Inn | ||||
| The Mystery of the Galloping Horse | 1973 | 20 | 208 | |
| The Clue of the Phantom Car | 1973 | 21 | 208 | |
| The Secret of Skeleton Island |
| # | Title | Year | Chapters | Pages | |
|---|---|---|---|---|---|
| 1. | Dødningeøyas Hemmelighet | ||||
| 2. | Coloradomysteriet | ||||
| 3. | Det Mystiske Fingeravtrykk | 1954 | 17 | 144 | |
| 4. | Diamantsmuglerne | 1954 | 21 | 136 | |
