Young adult novel about an agent for British Intelligence who is trying to find the secret device that allows free movement underwater. The jacket has a bright and attractive collage of danger and mayhem in color. Some minor soiling and small stains to the cover with rubbing to extremities and one 1/2" tear, now protected with acid-free polyester sleeve. Pages are crisp, clean and bright. . 8vo 8" - 9" tall. 222 pages. Science Fiction Suspense Spy Juvenile