In 1966, Lyndon Baines Johnson received the most alarming and unexpected briefing of his presidency. The two deep-underground nuclear detonations were not initiated neither in nor out of the nuclear club of sovereign nations. Three possibilities had emerged. Aliens. Nations as theorised by Edmond Halley's postulation that the Earth was hollow. Or the singularity that penetrated the Earth at the Tunguska Event in 1908.