An elegantly filmed documentary, Planet Ocean takes us on a beautiful adventure into the strangest domains of our planet - the oceans. The film features both the magnificence and the exposure of Earth's oceans. The dangers that threaten the whole planet also threaten us. We are guided through various series of events (sailfish relying on mackerel; mackerel relying on zooplankton; zooplankton relying on marine prairie) it is not simply to demonstrate the function of a food chain, but to illustrate the way in which all life is intrinsically interconnected. What happens to our oceans happens to our selves.

The Basilosaurus, the first of the large whale species, is not a harmless plankton eater but a fearsome high speed hunter. And most frightening of all is the Megalodon, a gargantuan ancestor of the great white that makes its modern day relative look like a tuna.