Adrian Chiles converted to Catholicism ten years ago, but wonders whether his choice of church was an accident of birth and geography. If he had been born in Istanbul or Jerusalem, would he have been equally happy being a Muslim or a Jew? In this first episode, he visits the stunning Dalmatian coast, where he meets up with his Croatian mum and reveals how he got the nickname Holy Joe. Next stop is Istanbul, where he has fun in the Grand Bazaar before heading out on the Bosphorus with a Muslim fisherman. During Eid al-Adha, a major Islamic festival, Adrian struggles to watch the celebratory sacrifice. He travels to Jerusalem for the Jewish festival of Sukkot, and then moves on to Tel-Aviv to get drunk with a gay, atheist, Jewish celebrity chef. His final stop is an Evangelical concert by the Dead Sea, attended by Christians from all over the world.

This episode finds Adrian in Rome, riding the ubiquitous Vespa with his favourite priest, Father Gianni, on the pillion. The pair speculate on whether having a priest accompanying him to the pearly gates improves or damages Adrian's chances of entry to heaven. Adrian then joins the faithful in St Peter's Square to listen to the man he describes as 'chairman and chief executive' of his own religion. Later, an 80-year-old cardinal tries to remain unflustered as Adrian makes his first confession in eight years. It takes a while. He observes the Sabbath with a Jewish family, but his brief flirtation with Judaism is cut short when he learns that becoming a Jew is not quite as simple as wanting to join. He cooks with the nuns of Marseille, and visits a Roman Catholic school where 80% of the children are Muslims and where he declares the head teacher to be 'the most inspiring person I have ever met'.