Digital Fortress.

DIGITAL FORTRESS. Dan Brown. 1998/ 2004. Read by Paul Michael. 10 cds. 12 hrs. Audio Renaissance. 1-59397-563-5. $44.95. Cardboard; plot notes. SA

Readers who want to explore Brown before his popular Da Vinci Code get a chance to do so with this excruciatingly complicated 1998 novel. Digital Fortress is supposed to be an unbreakable code invented by Tankado, a disgruntled former employee of the National Science Agency (NSA)'s cryptography department. After making the program available on the Internet to anyone who wants it, Tankado tries to blackmail Trevor Strathmore, the deputy head, by threatening to sell the key to the highest bidder if the NSA does not reveal the existence of its high-powered code breaker, TRANSLTR, rendering it useless and wreaking havoc on the NSA, but protecting the privacy of computer users world wide. Before Strathmore can react, Tankado is assassinated.

Plots, counterplots, chases, cold-blooded murders, and complications of all kinds ensue. Pleasant-voiced Michael narrates admirably. While the listener might occasionally like to shake the characters to get them to pay better attention, Michael patiently takes the reader by the hand and leads them through long-winded crypto-computer-techno-babble and suspense that seems never to come to an end. Mary Purucker, Beverly Hills P.L., Beverly Hills, CA