7/8 How tides create opportunities for marine life, as dolphins play a deadly game of catch.
6/8 This programme focuses on the amazingly fragile ecosystems of the world's coral reefs.
5/8 Exploring the richest waters on earth, where the solar cycle drives an explosion of life.
4/8 A look at the survival techniques of creatures in the Arctic and Antarctic.
3/8 Looking at predatory skills of whales, dolphins, tuna, shark and rapier-nosed billfish.
2/8 David Attenborough looks at the strange creatures that live in the depths of the ocean.
1/8 This travels to the very depths of the seas, to reveal a spectacular variety of life.