In Chapter 20 of Disclosing the Secret the NSA agent Mr. Sabre returns to his base of operation located in the Nevada desert known as Section 4, or simply S4.

This five-level, ultra-secret underground facility is allegedly located approximately 10 miles (16 km) south of the US Air Force’s “operating location” near Groom Lake in Nevada (also known as Area 51). It has been reported to have been built into Papoose Mountain and on the edge of Papoose Lake. Its nine-hangar bay doors are built at 60 degrees and set flush with the side of the mountain, its colour and texture specifically designed to seamlessly blend in with its surrounding topography. Papoose Lake is the dry lake bed that sits at the toe of Papoose Mountain; built over it is a barely detectable tarmac that leads to the hangar bay doors, facilitating the entry and exit of exotic craft hidden within.