| 1 | Hercule | Poirot | The famous Belgian detective. |
| | Mr. | Shaitana | Collects rare things. Hercule's friend. |
| 2 | Supt. | Battle | A top detective from Scotland Yard. |
| | Ariadne | Oliver | Detective
story writer. Mr. Shaitana's guest. Aka: Mrs. Oliver. |
| | Colonel | Race | Police colonel. Mr. Shaitana's guest. |
| | Geoffrey | Roberts | Physician. Mr. Shaitana's guest. |
| | Mrs. | Lorrimer | First class bridge player. Mr. Shaitana's guest. |
| | Major John | Despard | Tall, sporty, handsome man. Mr. Shaitana's guest. |
| | Anne | Meredith | Pretty woman. Mr. Shaitana's guest. |
| 4 | Anderson | | Police officer on duty. |
| 9 | Dr. | Emery | Dr. Roberts's partner. |
| | Miss | Burgess | Dr. Roberts's secretary. |
| | Mrs. | Graves | Dr. Roberts's patient. |
| | Dr. | Lee | Mrs. Grave's second doctor. |
| | Dr. | Steele | Mrs. Grave's third doctor. |
| | Dr. | Farmer | Mrs. Grave's fourth doctor. |
| | Mrs. | Craddock | Hysterical woman. Dr. Roberts's former client. |
| | Bank | Manager | Superintendent talked to regarding Dr. Roberts's bank account. |
| 12 | Rhoda | Dowes | Anne's friend who's living with her. |
| | Sven | Hjerson | Mrs. Oliver's fictional character. |
| | Mr. | Bury | Solicitor. |
| | Mr. | Myherne | Major Despard's first class lawyer. |
| 14 | Mr. | Pickersgill | Former owner of Anne's house. |
| | Mrs. | Artswell | A loquacious lady. |
| | Major John | Meredith | Anne's father. |
| | Mrs. | Eldon | Anne's former boss. |
| | Emily | Deering | Rhoda's aunt. |
| 16 | Sergeant | O'Connor | Police officer of Scotland Yard. |
| | Elsie | Battle | Parlourmaid of Mrs. Craddocks. |
| 19 | Timothy | Luxmore | The celebrated botanist. Deceased. aka: Professor Luxmore. |
| | Mrs. | Luxmore | Professor Luxmore's widower. |
| | Inspector | Japp | Police inspector from Scotland Yard. |
| 22 | Inspector | Harper | Police inspector in Devonshire. |
| | Mrs. | Benson | Anne's former employer. Deceased. |
| 28 | Dr. | Lang | Mrs. Lorrimer's doctor. |
| | Dr. | Davidson | Divisional surgeon. |
| 29 | Constable | Turner | Police officer. |
| 30 | Stephens | | Witness. Young actor. aka: Gerard Hemingway. |
| | Charles | Imphery | Home office analyst. |
| | Charles | Craddock | Mrs. Craddock's husband. |
