Bob Lazar appeared in a 1989 KLAS-TV interview with reporter George Knapp claiming employment at a classified facility near Area 51 called S-4, where he alleged he reverse-engineered recovered non-human craft and described an antimatter reactor powered by 'Element 115.'

Lazar's claims about S-4, propulsion physics, and Element 115 (later synthesized as moscovium with very different properties than he described) have never been corroborated by any government record or independent witness. The interview itself happened, KLAS aired it, and it has been reproduced exhaustively, but the substantive claims live entirely in Lazar's own testimony.