First "Microcosmos" examined the insect universe, then "Winged Migration" flew with birds, and "Planet Earth" took us to the remotest corners of the world. The visual splendors of "Oceans" are up next, reaching theaters, and not by coincidence, on the 40th anniversary of Earth Day.

What French filmmakers and "Winged Migration" veterans Jacques Perrin and Jacques Cluzard have achieved is both more surprising and more difficult than might be immediately apparent.

It's not only that spending four years going far under water presents physical challenges, its that fish are neither as automatically heart-tugging as "Planet Earth's" land animals nor as easy to find a story line for as those determinedly migratory birds.

And, in fact, "Ocean's" voice-over narration, read by Pierce Brosnan, is the film's weakest link, suffering, as did an early version of the "March of the Penguins" script, from its proximity to an overly poetic French style of nature narration. Where is the spirit that inspired the title of Jacques Cousteau's classic "The Silent World" when we need it?

But once "Oceans'" exhilarating visuals get going, its easy to ignore the words. This really is a film that manages to show us things we've never seen and make what we have seen look different and new.

Take, for example, the mobula rays, which waft like oceanic kites, or the exquisite cape that the blanket octopus releases when it feels threatened, or the remarkable grace of a sea slug called the Spanish dancer. These really do have to be seen to be believed.

"Oceans" is equally good at sea folks everyone is familiar with. The filmmakers constructed special equipment to film a pod of spinner dolphin leaping casually out of the water, let us marvel at a dozen humpback whales breaching at the same time and reveal what starfish look like when they are walking across the ocean floor on the tiniest of tubelike feet.

Like any nature documentary worthy of the name, "Oceans" does not stint on what might be called fang and claw stuff. We see newborn baby sea turtles consumed by diving frigate birds, watch a great white shark swallow a seal in one gigantic bite and two armies of fierce-looking spider crabs collide for no apparent reason.

Given that it is partially funded by Participant Media, a company that believes in films making a difference in the world, its not a surprise that "Oceans" makes a point of letting us know that "human indifference is the oceans' greatest threat," but the message is relatively soft-pedaled compared with more overtly political docs such as "End of the Line."

One of the unexpected pleasure of "Oceans" is the footage that runs alongside the final credits, showing camera people working far under the surface. Not only is it arresting to see humans in this environment, it is, to give one example, mind expanding to witness how tiny and puny humans are compared with a massive blue whale that might be 100 feet long. This is not just another world, its an alien universe, and we are privileged to get a look inside.

MPAA rating: G
Featuring: Narration by Pierce Brosnan
Credits: Written and directed by Jacques Perrin and Jacques Cluzard; produced by Nicolas Mauvernay and Romain Le Grand. A Disneynature release.
Running time: 1:24