Sue Perkins embarks on a breathtaking 1,500 mile journey along the Ganges, from its Himalayan source to the Bay of Bengal. In this first episode, she treks to the river's sacred origin, meets wandering holy people, and reflects on personal loss. From timeless Gangotri to spiritual Rishikesh and bustling Haridwar, Sue explores how modernity and mysticism collide - revealing a vibrant, changing India where devotion, commerce, and culture intertwine.