New York has never shied away from a little architectural drama—but the penthouse atop 111 West 57th Street is full-blown theater. Perched over 1,000 feet in the air, this four-story quadplex is the highest of its kind in the U.S., and at $110 million, it’s currently the most expensive home on the New York City market. The address? Billionaire’s Row, naturally.
Occupying the 80th to 83rd floors of the skinniest skyscraper on the planet, the 11,480-square-foot residence is…

