Reality TV will be plumbing new depths with the launch of an ambitious new BBC programme filmed one mile under the ocean.

BBC One's The Abyss - Live will see tiny submersibles scouring the darkness of the Pacific Ocean, off the coast of California, bringing back footage from depths that divers cannot reach.

The programme, which follows the success of documentary series The Blue Planet, will be broadcast largely live, capturing scenes such as shipwrecks and deep sea sharks.

It is one of the highlights of the �243m BBC One autumn schedule.

The Abyss - Live aims to bring viewers ocean scenes that are rarely seen on television because of the technology and skill involved in beaming back the footage.

Daniel Deronda is the latest adaptation of a George Eliot novel

Presented by Blue Planet producer Alistair Fothergill and Kate Humble, there will be two broadcasts from the deep during one evening.

"It will go right to the depths. No one has ever done this before," said a BBC spokesman.

"They will do some prerecording to supplement the live footage. We are fully confident it will all work on the night."

The BBC will mark the first anniversary of the 11 September attacks with several programmes including a documentary by Jules and Gedeon Naudet, who were filming a novice firefighter in New York when the World Trade Center was struck by two planes.

The channel is also set to devote a day to Cracking Crime, a project that will look at the impact of crime across the UK.

The programme follows on from the BBC One's day given over to examining the NHS.

Crimewatch presenters Nick Ross and Fiona Bruce will front the day of shows which will explore the reality and will allow viewers to vote for how tough sentences should be.

Drama

BBC One controller Lorraine Heggessey said: "Audiences want BBC One to move with the times, be more relevant, more contemporary, more challenging but they also do not want to lose the things they like best about the channel.

"The trick is to do both - and I think we're about half-way there. This season you're beginning to see BBC One as it should be with a well balanced mix of programmes."

Jeremy Bowen will turn his attentions to Moses

There will also be a lavish new period drama - an adaptation of George Eliot's novel Daniel Deronda - starring Hugh Bonneville, who starred in Iris, and Celia Imrie.

Harry Enfield makes his return to the BBC in the sitcom Celeb, which sees him play aging rock star Gary Bloke alongside Amanda Holden as his trophy wife.

Another new comedy, Wild West, comes from the pen of Men Behaving Badly creator Simon Nye and stars Dawn French as a post mistress in a wacky Cornish village.

And the ancient world of Egypt will be explored in Pyramid, using digital technology used to such great affect in the Oscar-winning Gladiator.

Palin explores

Digital viewers will be able to take part in what is claimed to be the world's first interactive TV adventure story.

Veteran broadcaster Sir David Attenborough will celebrate 50 years in broadcasting with Life of Mammals.

And BBC Breakfast presenter Jeremy Bowen will once again be tracing some of the most famous steps in history as he goes in search of the story of Moses.

He previously examined the life of Jesus in a documentary which mixed old technology with new, including creating a computer generated image of Christ.

Actor and explorer Michael Palin also goes back on the road, this time undertaking an epic journey in the Sahara.