This story is narrated by the baffled and suspended inspector of police Ms. Dhagini to a fellow passenger in a night train to spend that boring night and for redefining case for herself mainly. Her sleepless night was spent by narrating her experience of investigating the consecutive murders of Mathew villa.
At a point the Mathew villa case came to an end but she thinks, the lady Mrs. Berlin Jamshed Mathew, who had been arrested as a murder criminal is not actually a criminal, and something was petrifying her that an innocent is being punished.
The author says the readers about every stages of her investigation. Initially she had doubt within the family but when her view turned on the servant she dug up many information that even connected to a politician which led to her suspension, the story goes by a series of many twist and turns with Dhagini being suspended for silly reason.
Though she had suspended, she re-entered the case unofficially with the help of her colleague Arjun, sub inspector of police. She came back with determination to find the criminal. But unfortunately the prime suspect to investigate, the servant, was died in a cardiac arrest. Dhagini stood clueless and hopeless but her untiring effort gave her a clue of a letter envelope that had a name as Dr. John Juniville Thomas which she found at the servant’s house and she had an epiphany that she had seen the name somewhere else.
After many hindrances and frustrations she found that her fellow passenger is the prime criminal Dr. John Juniville Thomas and travelled with her to just know about her and to kill her. The thrilling and unexpected climax tells us about how sub inspector Arjun helped behind the scene, letting all the crime to happen and stood with his sister Mrs. Berlin Jamshed Mathew, the one who Dhagini thought as an innocent.
The intellectual Dhagini opened her third eye to close the case.