Monster barrel reveals its secrets

Check out this impressive footage of a South Pacific wave filmed by the BBC as part of their new series which shows for the first time unique action of a wave inside the barrel. (Words courtesy of the BBC)

"A huge ocean wave has been filmed from beneath the surface, revealing features never before captured on camera.

The remarkable video, which will be shown as part of the BBC Natural History Unit's new series South Pacific, was filmed in super slow motion using a high-definition camera.

It reveals the hidden power of a four-metre-tall monster barrel wave

It also shows the first images of underwater spiralling vortices created by the wave's action.

The wave was filmed off the coast of Pohnpei in the Caroline Islands, part of the Federated State of Micronesia.

The location is well known in the international surf community. Some of the biggest waves in the world break on South Pacific islands.

The storm swells that create these waves travel more than 5,000km to break on their shorelines.

Super slow mo

"I really wanted to slow the wave down, so it was like being there, immersed in that environment," says the BBC's Huw Cordey, series producer of South Pacific.

"I wanted to capture the scale of the event."

Doing so took special skills and equipment. Australian cameraman Bali Strickland, renowned for filming expert surfers at some of the best surfing sites in the world, had to float in the water as the wave passed over him.

He filmed the wave using a £66,000 ($100,000) high-speed camera that captures the action at 20 times slower than normal speed, and in high definition.

South Pacific: Oceans of Islands will be broadcast on BBC Two from Sunday, 10 May 2009 at 2030 BST