| Surendranath | Bannerjee | Sergeant on the IPF, aka Surrender-Not |
| Dr. | Bird | Physician who treated Sen's injuries |
| Mrs. | Bose | Owner of the brothel |
| Marjorie | Braithwaite | Assistant to Dawson |
| James | Buchan | A very wealthy jute & rubber merchant, Scottish, friend of MacAuley |
| | Byrne | Red-headed Irish textile salesman also lodging at the Belvedere |
| Sir Evelyn | Crisp | Managing Director of the Bengal & Burma Banking Corp. |
| | Daniels | Taggart's assistant |
| Colonel | Dawson | Commander of Section H (secret police) |
| Sub-Inspector | Digby | Officer in the Imperial Police Force, reports to Wyndham |
| Amarnath | Dutta | Radical host of a revolutionists' meeting the night MacAuley was murdered |
| | Evans | Train driver |
| | Furlow | Murdered shopkeeper in the East End of London |
| Mohandas | Gandhi | Indian politician & activist for Indian independence |
| Annie | Grant | MacAuley's secretary |
| Reverend | Gunn | Calvinist preacher, friend of MacAuley |
| Dr. | Lamb | Pathologist |
| Alexander | MacAuley | Murder victim, high-ranking aide ("fixer") to the Lt. Governor |
| Superintendent | MacLean | Police officer in Serampore |
| Horace | Meek | New lodger at the Belvedere |
| Hiren | Pal | Murder victim on the train |
| Albert | Perkins | Railway conductor, senior guard |
| | Peters | A lawyer in Calcutta for a case, also lodging at the Belvedere |
| Dr. | Rao | Physician who tended to Wyndham's gunshot wound |
| | Remnant | Captain of a police launch |
| | Salman | Rickshaw puller |
| Benoy | Sen | Agitator for Indian independence, leader of Jugantor |
| Sir Godfrey | Soames | Head of the Landowners' Association |
| | Stevens | #2 aide to the Lt. Governor |
| Alfred & Albert | Stratford | Toughs under suspicion for Furlow's murder |
| Lord Charles | Taggart | Commissioner of the Police Force, a major in the army in WWI Wyndham's boss |
| Colonel & Mrs. | Tebbit | Owners of Royal Belvedere Guest House where Wyndham lodges |
| Sam | Wyndham | Detective Inspector Captain in the Indian Police Force, newly arrived in Calcutta from England, World War I veteran, narrator |
| Albert | | Owner/maitre'd of the Glamorgan Hotel restaurant |
| Anjali | | Devi's real name |
| Charlie | | Sam's half-brother, killed in WWI in 1917 |
| Das | | Fan (punkah) operator at Mrs. Bose's house |
| Devi | | Prostitute at the brothel |
| Eric | | Coal man on the train |
| Isobel | | MacAuley's wife, died of typhus |
| Lakshmi | | Prostitute at the brothel |
| Meena | | Mrs. Bose's maid |
| Parvati | | One of Mrs. Bose's girls who became pregnant & died from a botched abortion |
| Ratan | | Doorman at the brothel |
| Rosie | | Assistant at Furlow's shop |
| Sandesh | | MacAuley's manservant |
| Sarah | | School mistress, Wyndham's wife, died in the flu virus of 1918 while Sam was recovering from a war injury |
| Saraswati | | Prostitute at the brothel |
| Sita | | Prostitute at the brothel |
| Vikram | | Digby's snitch |
