Digital Forturess

Susan Fletcher, a brilliant mathematician and head of the National Security Agency's (NSA's) cryptography division, finds herself faced with an unbreakable code named "Digital Fortress", which is resistant to brute-force attacks by the NSA's 3 million processor supercomputer dubbed "TRANSLTR". The code is written by Japanese cryptographer Ensei Tankado, a fired employee of the NSA, who is displeased with the agency's intrusion into people's privacy. Tankado auctions the algorithm on his website, threatening that his accomplice "North Dakota" will release the algorithm for free if he dies. Tankado is found dead in Seville, Spain. Fletcher, along with her fiance, David Becker, a skilled linguist with eidetic memory, must find a solution to stop the spread of the code.