The novel is a profound contemplation of life as seen through the eyes of two female protagonists: a 54-year-old concierge and a precocious 12-year-old girl, both living in the same upscale Parisian apartment building. The concierge, who conceals her intelligence and passion for literature and philosophy from the wealthy tenants, and the girl, who plans to commit suicide on her 13th birthday due to her disillusionment with the world, form an unlikely friendship. Their lives are forever changed when a wealthy Japanese man moves into the building.

In this novel, readers are plunged into a fascinating and complex world beneath their feet, where an ant civilization thrives with its own sophisticated society, technology, and culture. The story intertwines the lives of these ants with the human world, particularly through the experiences of a family that inherits a mysterious apartment in Paris, which hides secrets linked to the ant empire. As the narrative unfolds, the book explores themes of coexistence, the nature of intelligence, and the intricate balance of ecosystems, challenging the reader to consider the world from an entirely different perspective and to question humanity's place within the grand scheme of life.