Digital Fortress

The author of the decade's super bestseller invites you to crack another code — ultra-complex, containing danger and threat to the entire world! 
But... who invented this call?! What is he trying to achieve?!
Why did he enter into a ruthless game with the U.S. National Security Agency?! 
The weapon of the mysterious enemy is merely a set of symbols and letters. 
The best cryptographer in America, Susan Fletcher, is tasked with deciphering it. 
And what she discovers threatens not only the most important developments of U.S. intelligence agencies but also the fates of millions of people... From this moment, a real hunt begins for Susan...