The ancient Egyptians were obsessed with divinity, death and the afterlife, and reincarnation. In this opening episode, host Christy Kenneally visits Saqqara, south of Cairo, where the Egyptians learned the technique of mummification and built the first pyramid – an early prototype for the grand monuments of the Giza pyramid complex. He journeys on to explore the ruins at Abydos, Karnak and Luxor, arriving finally at the island of Philae – the site of the last hieroglyphics and a little-known shrine to Egypt's lost gods.

Ancient Greece was the first major civilization to emerge in Europe. Its seat of power in Athens was crowned by the Acropolis, the famed city of the gods. In this episode, host Christy Kenneally explores the surviving remnants of this great civilization and its gods: Parthenon, home to the goddess Athena and the most spectacular of the monuments of the Acropolis; Delphi, the “Vatican” of ancient Greece, where the god Apollo spoke through his Oracle; and the Greek colony of Paestum in southern Italy, site of a temple to Poseidon.

The spectacular rise and fall of the Roman Empire fascinates us to this day (as evidenced by the success of films like Gladiator , and the HBO series Rome). The Romans took their gods from the Etruscans, on the ruins of whose civilization they built their own. In this episode, host Christy Kenneally visits the Forum, the epicenter of Roman religion, and the Pantheon, sanctuary of the Roman gods. In Caerleon in Wales, he reveals how the Romans carried their religion to the farthest reaches of the empire. And at Ephesus in Turkey, he traces the rise of the Christian deity that would ultimately overthrow the Roman gods.

The Maya believed they owed a blood debt to the Gods – one that could only be repaid through sacrifice. Deep in the rainforest of Guatemala, host Christy Kenneally explores the massive Mayan city of Tikal. In Mexico, he discovers the secrets of the spectacular temples of Palenque and Chichen Itza. And at the Island of Flores, Guatemala, he reflects on the final stand of the Maya against the invading Spaniards.

The Inca worshiped both a creator god and the sun, moon and stars. In this episode, host Christy Kenneally travels to the Peruvian Andes to explore the remnants of Inca civilization: the city of Pisac, which like all Inca cities was designed in the shape of a sacred animal; Cajamarca, where the Inca leader Atahualpa was murdered by the Spaniards; and the sacred mountaintop city of Machu Picchu.

The Celts believed in benign spirits and demonic forces, but made no churches or temples: nature itself was their cathedral. In this episode, host Christy Kenneally visits ancient Celtic settlements in Austria, Italy and Greece. He explores the settlement of Castell Henllys in Wales, where the religion of the druids was broken by Roman military might. And at Newgrange, Ferrycarraig and Dun Aengus in Ireland, he reveals how the Celts came to adopt the gods of those who had preceded them.