Programme and cast - About oceans

Oceans cover two-thirds of the surface of our planet. The seas, which are vital to survival, have remained an enduring part of our human story.

In June 2007 the Oceans team began a series of underwater scientific expeditions to build a global picture of our seas. Their search for answers took them on an voyage of discovery to the Arctic, Southern and Indian Oceans, the Atlantic, the Red Sea, the Sea of Cortez and the Mediterranean.

Explorer Paul Rose led the team of intrepid adventurers, including environmentalist Philippe Cousteau (grandson of Captain Jacques-Yves Cousteau), maritime archaeologist Dr Lucy Blue and marine biologist and oceanographer Tooni Mahto.

The team ventured into some of the planet's most challenging environments and with the help of scientists and dive teams, they descended beneath frozen Arctic ice-sheets, dived into mysterious black holes in the Bahamas and plunged into the dark water with the fearsome Humboldt squid.

The results are shown in this eight part series on BBC Two, which seeks to provide a better understanding of the state of our oceans today, their role in the past, present and future and their significance in global terms. Paul Rose documents just a few of the scientific observations his team made in this BBC News feature.