On Thanksgiving Eve 1971, a man in a business suit ordered a bourbon and seven-up, handed a flight attendant a note claiming he had a bomb, and then parachuted out the back of a Boeing 727 with $200,000, vanishing forever.

This episode unpacks the mechanics behind the legend of D.B. Cooper: the brilliant tactical planning, the bizarre physical evidence, and the central paradox of whether he was an aviation genius or a doomed amateur. From CIA-era aircraft features to spring-blooming diatoms, the case keeps shifting depending on the evidence.

• Why demanding four parachutes implied hostages and forced authorities to supply functional gear
• The specific flight parameters, 10,000 feet at 100 knots with flaps at 15 degrees, that exploited the 727’s aft airstair
• The clip-on tie analyzed in 2009, revealing rare titanium and rare-earth particles pointing to specialized work
• The 1980 discovery of $5,800 at Tina Bar and the geological mystery of sand dredged in 1974
• Copycats like Martin McNally and Richard McCoy Jr. who proved the jump was survivable