Rosie Goldsmith, who has a life-long fascination with the Virgin Mary, explores her power as an apparition and in visions around the world. Mary is a global symbol. She's also a figment of wild hallucinations. Her face is on T-shirts and jewellery. Modern-day apparitions have been spotted in fruit bowls and on pieces of toast and filmed on mobile phones. Thousands of websites are devoted to her and millions of people still travel hundreds of miles to worship at her shrines, to pray for health and happiness. But many people argue that Mary is just one big con trick - a poetic myth-maker for the Catholic Church, a hallucination created in the minds of the ill and the vulnerable. In this programme Rosie talks with Richard Dawkins, Ann Widdecombe, Marina Warner, Mark Dowd, Susie Orbach and Miri Rubin and asks how they reconcile an often holy madness with today's need for multi-faith balance? At the Knock shrine in Ireland a woman reveals how Our Lady cured her as she was dying. An expert on 21st century Cyber-Mary explains how the internet is today the most powerful weapon in whipping up Mary fervour. And a young American student describes witnessing the apparition of Mary in a hospital window in Massachusetts. Producer: Sarah Cuddon A Falling Tree production for BBC Radio 4.