Antar is a man living in New York sometime in the future. He is nearing retirement, and works for the International Water Council as an analyst. He works from his home because his work is deemed inconsequential. 

Murugan, or Morgan, as he is sometimes referred to, worked for Life-Watch in the 1990s, until he disappeared in 1995. He was an authority on Ronald Ross, the man who discovered the cause of malaria. 

Urmila is a young woman who works as a journalist for Calcutta magazine. Not long out of school, she lives at home with her parents, siblings, and extended family. Her income helps the family, but her family, particularly her mother, doesn’t see a future for her as a working woman. 

Sonali is also a writer for Calcutta magazine. It’s the first job she’s had in years, having lived off her early fame as an actor and writer, and her mother’s fame as a legendary stage actor. She’s older than Urmila and her father is Phulboni. 

Phulbani is a famous author who first came across the name Laakhan as a young man, when he was sent to Renupur as a representative of the Palmer Brothers company. Phulboni was once a close friend of Sonali’s mother, and is the father of Sonali. It’s Phulboni who speaks of the secrets that lie in Calcutta, who refers to the mistress of Silence, and who has dedicated his life and writing to finding her. He was known to wander the streets of Calcutta at night, searching for this mistress.

Phulboni wrote many stories, including a series of stories depicting Laakhan as a character who was constantly changing his identity and name.

Ronald Ross was a British poet, novelist, and scientist. Ross was born in 1857, in India, and awarded a 1902 Nobel Prize for his work with the malaria parasite. Ross’s role in discovering that malaria is transmitted via certain mosquitoes is central to the plot’s unfolding. 

Lutchman, also known by the name of Laakhan, is one of the novel’s antagonists. His character is elusive. Lutchman was a dhooley-bearer who worked for both Cunningham and Ross. Murugan has suggested that it was Lutchman who pushed Ross in the right direction, leading to Ross’s breakthrough on what causes malaria. It apparently was also Lutchman who gave Farley the slide containing pigeon’s blood handed to him by Mangala. Grigson, a linguistic surveyor, believed Lutchman was from much farther north than he had let on, a place where his name was likely Laakhan. It was said that Lutchman had difficulty using his left hand.

Laakhan is the prime incarnation of Lutchman. However, he remains an unknown character. In the story, we never get to really know him. His name has been mentioned over the course of many events, in many locations for more than a century. He is also dangerous. He is said to be the young man last seen before Farley went missing. 

Mangala first appears as a poor sweeper-woman, who D.D. Cunningham found, along with Lutchman, at the Sealdah station in Calcutta. She is also, like Lutchman, an antagonist in the story. In Farley’s letter, he describes how he witnessed Mangala informing the young man bringing the slides to Farley on which slides to take to him, clearly demonstrating significant knowledge about malaria, even though all others assume she’s had no schooling of any sort.