A disturbed grave in a century-old cemetery. A ciphered message. A mysterious `repeater’… On a visit to the Park Street cemetery in Calcutta, Feluda and his friends chance upon an old grave that has been dug into. Slight clues lead them into the heart of a mystery that is both complex and blood-curdling. When the jigsaw that involves a seance in a gloomy old building, a singer in a restaurant, a ruthless and rich collector and a midnight vigil at the graveyard is put together, what emerges is one of the most intriguing mysteries Feluda has ever been faced with.