On New York’s Upper West Side, beneath the fictional Arconia building, is a secret space: The Velvet Room—an opulent underground gaming parlor hidden below the building's courtyard. The Gilded Age engineering required such substantial underground infrastructure that many Manhattan buildings contained cavernous spaces perfect for clandestine purposes—from speakeasies during Prohibition to private gambling dens like the fictional Velvet Room. The color palette in the Velvet Room connects the underground space to the building's established look. "There are some that you will see in the gaming room and some that you will see in other characters’ sets," he teases. For devoted fans who've spent five seasons analyzing every apartment detail for clues, the Velvet Room represents the ultimate payoff.