The Herald of Free Enterprise is a new class of ferry that allows cars to drive directly into the ship. The doors must be closed before every departure, or the ship sails with a gaping hole at one end. One black night in 1987, on the freezing waters off Zebrugge, Belgium, a single crew member falls asleep at the worst possible time.
For the sources, see the show notes at timharford.com

"What a Bloody Mess we're in" - Britain's [REDACTED] Accident
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Attack of the Night People
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