From the burrows and secret bunkers beneath our feet to imagined hellscapes and surrealist dreamscapes, the disquieting, alarming,and wonderful visuals span natural and constructed subterranea and imagined and subconscious worlds. The works of art featured range from the scientific and photographic to the surreal and visionary. A personal introduction by Ellcock together with contextual chapter introductions establish key themes while panel texts elucidate essential concepts, historical events, and figures. Thought-provoking literary, philosophical, and spiritual quotations punctuate the intriguing images.Together, the arresting images and authoritative text highlight the interplay between the real and the imagined, revealing how the real has informed our imagination, and conversely how our imagination has depicted the esoteric, the abject, and the unknown.