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 little-known amateur footage of the crash has resurfaced, 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.