The cause of the infamous Hindenburg crash has baffled experts for over 80 years, with theories about the airship's fire ranging from deliberate sabotage to a spark generated by the stormy conditions in which it landed. But new, never-before-seen amateur footage of the crash has surfaced, showing the airship's final seconds from a fresh angle and in unrivaled clarity. Taking clues from the footage and other sources, NOVA leads a fresh investigation at a leading scientific lab with eye-opening experiments that point to a final solution of the mystery.

Five centuries ago, the Age of Exploration and Europe's imperial colonization of far-off lands was launched by a revolution in ship design that made long-distance ocean voyages practical. But exactly how this momentous innovation happened eludes historians. Now, the excavation of a rare intact wreck discovered off the coast of Sweden offers vital new clues to a maritime mystery. 

Along with other clues gleaned from the wreckage, the figurehead and gun carriages suggest that this could be the flagship of a Danish king named Hans. The monarch was famous for building a large naval fleet, led by a massive warship known as the Gribshunden, the Griffen Dog.