Shallow Seas follows a humpback whale and calf on their epic journey across the richest seas that fringe our coasts. From tropical paradises, where the newborn calf takes his first faltering breaths, to the storm-ravaged icy polar seas, the whales' great feeding grounds, we reveal seas of great contrast and surprise.

In tropical Indonesia we discover the richest coral reefs of all, home to creatures more of fantasy like the head-butting pygmy seahorse, flashing 'electric' clam and bands of 30-strong sea snakes, never filmed before, on the hunt.

In the baking deserts of Arabia, we uncover mysterious giant colonies of seabirds and in Australia ingenious surfing dolpins that have learned to hydroplane right up onto the beach to catch their fish.

New underwater timelapse photography reveals extraordinary events normally too slow to register - like plagues of sea urchins felling great aquatic forests of giant kelp and giant star fish on the rampage, monsters in their world.

And we witness the heart-stopping drama of gigantic bull fur seals attacking king penguins, who despite their severe weight disadvantage, put up one of the most spirited defences ever filmed.