S2·E12 Insane Inventions

From personal jetpacks that promised to send us sky-high, to electrified exercise machines that shocked us into shape, to firefighting hand grenades hurled straight into the flames, yesterday's boldest inventions were packed with promise - and risks nobody saw coming. These are the ambitious ideas, futuristic gadgets, and engineering marvels that aimed to revolutionize everyday life, but sometimes overshot the mark.