In the sewers of Bergen, a microbiologist investigates a possible contamination of the city's drinking water. A poem reveals a hidden presence dwelling deep beneath the city. The poem speaks of a witch who manipulates the water, seeking a successor to spread her influence. It warns of the witch’s lair and her desire to train a child in her dark ways, corrupting the water with each passing day. The poem cautions against venturing too far into the sewers, where the witch reigns supreme in perpetual darkness.