Crack in the World (1965)

An international consortium of scientists, operating as Project Inner Space in Tanganyika, Africa, is trying to tap into the Earth’s geothermal energy by drilling a very deep hole down to the Earth’s core. The scientists are foiled by an extremely dense layer of material at the boundary between the two. To penetrate the barrier and reach the magma below, they intend to detonate an atomic device at the bottom of the hole.