Perch of the Devil is about the hard rock miners of Butte, Montana, and the strike of copper miners in l959. The film reviews the history of the Mine, Mill and Smelter Workers Local Union No. 1 and the many violent struggles that have happened in the mining camps of the western Rockies. There are interviews with miners, and with victims of silicosis, a fatal lung disease among miners. The film also contains footage of mining operations in tunnels a mile below the surface.