Visibility Zero (S08E41)

In 1993, the Amtrak Railroad experienced the deadliest train crash in United States history, when the Sunset Limited derailed while crossing Alabama's Big Bayou Canot bridge. Forty-seven passengers and crew were killed; scores more were injured. The clues to the cause of the crash lay etched in twisted steel and buried in the mud of the Big Bayou Canot. (Prime Video)