Well, if you like 20C autobiography and you are interested in crypt, then you'll like this. Peacock is an emeritus professor of economics (with whom I once shared a room in 197x) and writes as such: very entertaining but scholarly. As the blurb says, and Peacock stresses, the book avoids the very well trodden territory of Bletchley Park etc, and tells an unknown tale of front line crypt under fire at sea. An entertaining mix of technical stuff you don;t know, interspersed with some service anecdotes that often make you laugh. All articulately written.