Seven celebrities of differing faiths and beliefs experience an emotional journey on a pilgrimage in north Wales, a route linked by churches dedicated to early Celtic Christian saints.

Immersing themselves on this spiritual journey are wildlife presenter Michaela Strachan, who places her faith in the natural world; Spencer Matthews, a former Made in Chelsea reality star who was christened in the Church of England but is still searching for answers to life's big questions; Sonali Shah, a journalist and TV presenter who grew up in a Jain family; comedian Eshaan Akbar, a lapsed Muslim; Amanda Lovett, a practising Catholic who was catapulted into the public eye in the first series of Traitors; actor Tom Rosenthal of Friday Night Dinner fame, who is irreligious; and TV personality and former model Christine McGuinness, who is spiritual but doesn't practise one particular faith.

Travelling on foot and by bus, the seven pilgrims begin their adventure at Flint Castle on the bank of the Dee Estuary and follow the coast path to Greenfield Valley, the official start of the 220km Pilgrim's Way.

The pilgrims' final destination is Bardsey Island, the fabled ‘Island of 20,000 Saints'. Along the way, they see spectacular landscapes, visit holy sites and engage in fasting, ritual and meditation.