| Clue | Source | Date |
|---|---|---|
| Famous film? Helena noted it being broadcast around hotel (5,2,3,4) | ||
| Edit tenth headline about old mystery | The Telegraph Toughie | 12 Jun 2020 |
| *Fifteenth Hercule Poirot novel | Wall Street Journal | 16 Mar 2019 |
| *Fifteenth Hercule Poirot novel | ||
| Classic Poirot case | ||
| 1978 Peter Ustinov film | ||
| Classic Poirot case |