Climbers have invented a new safety gadget, the skyhook, a small piton which instead of penetrating cracks in the rock is placed on small apertures or an almost smooth rock surface. The precariousness of this obliges the mountaineer to move carefully, any sudden movement may easily dislodge the skyhook and provoke a fall. The film is educational and shows a mountaineer climbing a dilapidated church and then a wall. He carries out dangerous experiments to demonstrate ways in which the skyhook should not be used.