Blue Planet II, premiering this Saturday on BBC America, is one of those astounding TV events to make special plans to watch, record, and treasure. I can’t quite wrap my head around the new technology, and infinite patience, that allowed the filmmakers to catch such glorious, jaw-dropping images and events. BBC America is doing its best to get viewers involved in advance, by repeating, in daily marathons, its best nature documentary series of this century to date. Yesterday, the network re