Explore the depths of the oceans and discover some of the planet's most spectacular species. From the humble huddling of schools of bait fish to the bioluminescent defense of vampire squids, the program investigates predator-prey relationships and the harsh realities of life underwater. The endangered status of the blue whale, the largest animal to ever exist, shows both the strength and fragility of the natural world and raises questions about the importance of wildlife conservation. Running time: 42 minutes. Available to U.S. Customers Only.