The narrative begins in the guarded villa of General Trebassof, a relentless military man marked for assassination by revolutionary factions following the violent suppression in Moscow. Despite a heavily fortified perimeter and the watchful eyes of the police, mysterious attempts on the general's life continue to occur from within the locked house, suggesting a betrayal by someone close to the family. Rouletabille arrives in Russia at the personal behest of the Tsar to unravel the escalating enigma, quickly dismissing the official police guard to allow the hidden threat to reveal itself naturally.
As the household maintains an unsettling pretense of festive gayety, the plot develops around the complex psychological dynamics between the general's loyal second wife, Matrena, his serene and enigmatic stepdaughter Natacha, and his two military aides, Boris and Michael. While the general grapples with agonizing insomnia and haunting memories of the past, Rouletabille conducts a subtle investigation, discovering a clandestine passage used by an intruder through a servant's stairway and uncovering an attempt to poison the general's sleeping potion.
Tensions mount as the investigation reveals that the threats do not merely come from outside nihilist cells, but are intertwined with personal loyalties and hidden motives within the domestic circle. Rouletabille traces suspicious movements to a nearby villa in Krestowsky, connecting the local disturbances to figures linked to revolutionary cells and personal vendettas. The narrative explores themes of blind devotion, political fanaticism, and the psychological burden of violence.
The investigation reaches a climax during a night of suspense when an intruder is finally caught in the act of breaching the general's chamber. The subsequent confrontation exposes the shocking identity of the saboteur within the trusted staff, shattering the fragile peace of the datcha. Although the immediate physical danger is thwarted through Rouletabille's acute deductions, the resolution leaves lingering shadows regarding the true depths of the conspiracy against the general.
