A brilliant new natural history series is set to delve deep into the rich wildlife of Cardigan Bay and the Welsh coast.

Narrated by Dame Siân Phillips, Wonders of the Celtic Deep, airs on BBC One Wales at 9pm (Tuesday, October 12).

The Teifi estuary also features prominently in the first episode, capturing an array of species in Ultra High Definition.

Made by some of the film-makers behind natural history series Blue Planet, many new discoveries were made.

Cameras captured some remarkable and exciting new behaviours that have never been filmed in UK waters.

It includes the courtship rituals of bottle nosed dolphins in Cardigan Bay as they seek a mate using a unique dialect.

"I feel so privileged to be a part of this life-changing series," said Dame Siân Phillips.

"As for the beauty and the wonder of it - it shows us things never before filmed.

"These film makers have an eye for the wit and humour as well as the tragedy of life in the Deep".

Rhuanedd Richards, Head of Content and Services BBC Wales says: "Who isn’t enthralled by the wonders of our seas and the fascinating creatures that lie beneath them?

"For many of us, this secret world is shrouded in mystery but this wonderful new series guides us expertly through what lies beyond our Welsh shores."

She adds: "This series is available in Ultra High Definition which gives the viewer a remarkable viewing experience.

"The marvellous music composed by Paul Mealor and expertly performed by our very own BBC National Orchestra and Chorus of Wales takes this series to the next level. It really is fantastic."

Wonders of the Celtic Deep is a One Tribe TV production for BBC Wales.

The series has been part-funded by Creative Wales, an agency that promotes the growth of the creative sectors across Wales.

Welsh Government Deputy Minister for Arts and Sport, Dawn Bowden, said: "We are delighted to support a real first for the creative industries in Wales.

"Wonders of the Celtic Deep is celebration of Welsh creativity – a stunning orchestral soundtrack created by a Welsh composer, voiced by a Welsh legend and filmed across some our country’s most stunning coastal locations.

"One Tribe TV has created a stunning piece of work that I hope viewers will enjoy."