In 1845, explorer Sir John Franklin set sail from England with two ships, HMS Erebus and HMS Terror, in search of the fabled Northwest Passage that would connect the Atlantic and Pacific, across what is now the Canadian Arctic. The ships and crew were last seen by Inuit on King William Island, then vanished without a trace.

Frozen in time for almost 200 years, it wasn’t until 2014 that a Canadian mission, equipped with all the latest marine archaeological equipment, located Erebus. Terror was discovered two years later.

NOVA is on board as a Canadian team makes a breakthrough discovery of one of Franklin's lost ships and a vital new clue to the ill-fated expedition that only the ships can solve.