NOVA presents "Arctic Ghost Ship" an exclusive breakthrough in the greatest unsolved mystery in Arctic exploration. In 1845, British explorer Sir John Franklin set off to chart the elusive Northwest Passage, commanding 128 men in two robust and well-stocked Royal Navy ships, the Erebus and Terror. They were never heard from again. Eventually, searchers found tantalising clues to their fate: a hastily written note left on an island, exhumed bodies suggesting lead poisoning, discarded human bones with marks of cannibalism and Inuit legends of ghost ships. But no trace of the ships was ever found. Then, in 2014, after seven years of searching, an official Parks Canada expedition finally located the Erebus, intact and upright on the sea floor. With exclusive access, NOVA tells the inside story of the risky Canadian expedition, which involved constant battles with crushing sea ice, bad weather, and disappointing dead ends. Culminating in the historic discovery of the Erebus, NOVA tells the gripping story of the ill-fated expedition and reveals exclusive new clues from the sea floor that may finally unravel what happened to Franklin's men more than 160 years ago.