Two congressmen vanish in Alaska in 1972.

Battling snow and waves, searchers hunt for the missing plane.

A mysterious assassination letter surfaces.

The pilot’s account of a previous Arctic crash.

A mobster marries the widow of one of the missing men.

A shocking story, as told to investigators in 1994.

A cabbie kills a key player, and investigators dither.

“Dateline N.B.C.” commissions a secret report.

Jon and Paul crisscross the desert, chasing clues.

Through two photos, Jon untangles a mafia web.

One man who heard the bizarre broadcast is alive.

The team lands in Alaska and gets to work.

A critical clue leads to an island in Alaska.

Back in Cordova, the search party buzzes Bob.

An icy ending seems less likely as new details surface.

A new account of the alleged bombing, via a serial killer.

We locate the first known photos of N1812H.