In his documentary film, Karl Saurer recounts the history of Switzerland's largest reservoir, located near Einsiedeln in the canton of Schwyz. The film brings to life the landscape of the vast Sihl plain, which was flooded in 1937 to generate electricity for rail transport. The dam affected the livelihoods of more than 1,700 people; 107 farms were flooded. Saurer tells a story of colonialism in central Switzerland. In his film, he paints a picture of this event and the associated contradictions and conflicts between the agricultural mountain region and the industrialized lowlands, regional and national aspirations, and economic and ecological interests. Old and new footage and conversations with construction workers and displaced farmers make it clear that the wounds left by the construction and concession in the high valley have not yet healed.