The release date for the English version of 'Enigma' by
Robert Harris is Sep 1996. If you enjoy this novel, it is available for buy as a paperback from Barnes & Noble or Indigo, as an ebook on the Amazon Kindle store, or as an audiobook on Audible.
Tom Jericho, a member of a top-secret British cryptographer team, breaks the operational cipher used by Nazi U-boats, "Shark," but Jericho has to break the new code before a traitor in his organization can stop him. The Germans update the code.