The Mohole Mystery

A drilling project in Dudley in the West Midlands region of the United Kingdom hits a cavern 20 miles beneath the surface of the Earth and detects strange microbes. U.N.E.X.A. send Russian Serge Smylov down to search for other forms of life in a rocket-propelled capsule but it is damaged when it hits the bottom of the cavern. Then strange creatures start attacking him...