The Mohole Mystery
Hugh Walters
 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. UNEXA 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... The book, under its US title The Mohole Menace, is mentioned in A Short History of Nearly Everything by Bill Bryson.