OUR oceans are vast, and teeming with life. They are beautiful, and terrible, and humbling in their power.

Yet at the same time they are desperately fragile. Last year, scientists revealed that the beaches of a single uninhabited island in the South Pacific - Henderson Island, in the Pitcairn group - were littered with about 37.7 million pieces of plastic.

All that beauty, all that majesty and all that terrifying fragility will be coming to a big screen near you next Tuesday.

The Banff Ocean Film Festival is touring the world. And it reaches the York Barbican, for one night only on Tuesday, in the form of a series of short films that explore the oceans' hidden depths and man's own relationship with the waters that cover two thirds of the surface of our world.

Many of the films have taken years to make. In The Big Wave Project, filmed over five years, a tight-knit crew of surfers set out with a single goal: to ride the world's biggest wave.

Husband and wife team Eusebio and Christina Saenz de Santamaria, meanwhile, are champion free-divers, trained to dive without supplementary oxygen. Self-taught photographers based on the tropical island of Koh Tao, Thailand, they're masters at exploring and photographing the ocean depths on just one breath of air. The five-minute short film One Breath shows just how extraordinary the results can be.

In Kiwi Breeze, a London-based New Zealander spends nine years building a yacht in the back garden of his South London home ...then sails it the 15,000 miles back to New Zealand.

There's beauty and peril and adventure aplenty in all these films. But it is the 32-minute short Blue that will stop you in your tracks. The multi award-winning film sets out to chart the drastic decline in the health of our oceans. With more than half of all marine life lost and our seas becoming ever more industrialised, the film sets out the challenges we are facing ... but also the opportunities we still have to do something before it is too late.

The film includes some heartbreaking images - the skeleton of a green turtle washed up on a beach on Australia's Cape York Peninsula, still wrapped in the net which killed it; a river in the remote jungles of Bali, banks lined with plastic litter. But it also introduces some of the people who are defending habitats, combating marine pollution and fighting for the survival of key marine animals. There's still hope, even now...

Stephen Lewis

The Banff Ocean Film Festival, York Barbican, 7.30pm, Tuesday October 23.

Tickets £12.45-£14.61 from oceanfilmfestival.co.uk