For folks used to watching the beautiful undersea imagery from the likes of the "Blue Planet" (2001) or it's 2017 sequel, this might seem a little bit unremarkable - but if you watch this documentary on this visionary man, you will soon realise that he and his "oceanic musketeers" were the source of so much of the basic building blocks upon which the latter programmes are based. From designing the "Aqualung" to pioneering waterproof cameras, this Frenchman comes across here as a forward thinking and inspirational figure. Of course he had flaws - much of what he did was funded by and produced…