| | | | Part 1 |
| | Stephen | Farr | Ebenezer's son. The guest at Lee's Christmas Party. |
| | Pilar | Estravados | Simeon's only granddaughter. Jennifer's daughter. |
| | Alfred | Lee | Lydia's husband. Simeon's son. |
| | Lydia | Lee | Alfred's wife. |
| | David | Lee | Simeon's son. Alfred's brother. |
| | Hilda | Lee | David's wife. |
| | George | Lee | Alfred's brother. Simeon's son. |
| | Magdalene | Lee | George's wife. |
| | Tressilian | | Simeon's butler. |
| | Harry | Lee | George's brother. Simeon's son. |
| | Simeon | Lee | The old millionaire. Victim. |
| | Mr. | Charlton | Simeon's lawyer. |
| | | | Part 2 |
| | Walter | | The footman. |
| | Ebenezer | Farr | Stephen's father. Simeon's former business partner. |
| | | | Part 3 |
| | Mr. | Sugden | The superintendent of police. |
| | Colonel | Johnson | The chief constable of Middleshire. |
| | Cartwright | | The victim on Poirot's last case. |
| | Hercule | Poirot | The famous Belgian detective. Protagonist. |
| | Juan | Estravados | Pilar's father. Jennifer's husband. |
| | Doris | Buckle | The young lady at the box office. |
| | Major | West | Sydney's former boss. |
| | Jasper | Finch | Sydney's former boss. |
