On February 27, 2026, Maj. Gen. William Neil McCasland walked out of his Albuquerque home and did not come back.He left his phone. His glasses. The wearables that should have painted his last hours in data. He took a wallet and hiking boots. A .38 revolver that family said should have been there was not.McCasland was not a private citizen who wandered off a trail. He was the retired commander of the Air Force Research Laboratory at Wright-Patterson—the shop that sits on American aerospace, materials science, and the programs officials will only discuss in half-sentences. His case did not stay local. It pulled in the FBI, congressional staff, and a public already watching a grim run of vanished and dead researchers tied to Los Alamos, NASA JPL, and nuclear-adjacent labs.Jack Cary treats the file the way an investigator should: objects, dates, institutions, and the gap between official language and rumor. The Vanished Vanguard is not a verdict. It is the record of what happens when a classified life meets daylight—and the daylight is not enough.