One day in June, two young people apply for a job in a mysterious building on the "billionaire's row" of 57th Street in New York City. Unlike the other skyscrapers on the street, 211A West 57th is a self-contained universe built for single family, who are unknown to most of its inhabitants. There are schools, farms, restaurants, libraries, theaters, a hospital, industries, high, middle and low-income apartments, laboratories, gyms, markets, chapels, its own post office, a bank and 15 forbidden floors, off-limits to the residents. It is a world fueled by gossip, animated by scandal and powered by an unseen force. The building is capped by a glass dome enclosing a magnificent aviary, filled with exotic birds, including a world-renowned collection of hummingbirds. On the day the new employees are hired, the aviary is in turmoil. A rare hummingbird has gone missing. The two find themselves swept up in the search and caught in a flood of events that almost destroys the building, revealing its deepest secrets and threatening the lives of everyone inside.