Gray Day - Eric O'Neill

Gray Day

By Eric O'Neill

  • Release Date: 2019-03-26
  • Genre: Political Science
Score: 4
From 67 Ratings


A cybersecurity expert and former FBI “ghost” tells the thrilling story of how he helped take down notorious FBI mole Robert Hanssen, the first Russian cyber spy.

“Both a real-life, tension-packed thriller and a persuasive argument for traditional intelligence work in the information age.”—Bruce Schneier, New York Times bestselling author of Data and Goliath and Click Here to Kill Everybody

Eric O’Neill was only twenty-six when he was tapped for the case of a lifetime: a one-on-one undercover investigation of the FBI’s top target, a man suspected of spying for the Russians for nearly two decades, giving up nuclear secrets, compromising intelligence, and betraying US assets. With zero training in face-to-face investigation, O’Neill found himself in a windowless, high-security office in the newly formed Information Assurance Section, tasked officially with helping the FBI secure its outdated computer system against hackers and spies—and unofficially with collecting evidence against his new boss, Robert Hanssen, an exacting and rage-prone veteran agent with a fondness for handguns. In the months that follow, O’Neill’s self-esteem and young marriage unravel under the pressure of life in Room 9930, and he questions the very purpose of his mission. But as Hanssen outmaneuvers an intelligence community struggling to keep up with the new reality of cybersecurity, he also teaches O’Neill the game of spycraft. The student will just have to learn to outplay his teacher if he wants to win.
A tension-packed stew of power, paranoia, and psychological manipulation, Gray Day is also a cautionary tale of how the United States allowed Russia to become dominant in cyberespionage—and how we might begin to catch up.


  • Wasted Time

    By Maximus Hox
    Rarely do I not finish a book. I just couldn’t take this author’s style of meshing all his personal issues with a story that could be told in 5 minutes. This guy might have been a great FBI agent, but he’s a terrible story teller.
  • Real Life Thriller!

    By Wolfsrun33
    Finished in a weekend. This book is exceptionally written and is amazing because it is a true story. I also feel that after reading it, I am safer from cyber attacks :)
  • Must read if you like a thriller

    By njmiller3
    Might be the best book I’ve ever read.
  • 10/10

    By Elsa G$
    I loved this book. I have followed this story since it came out in the news. It is expertly written and easy to follow. It coordinates well with the movie Breach. I highly recommend this book to anyone who reads true crime/cybercrime/spy genres