In 1986, Cliff Stoll noticed a $0.75 accounting error on the computers he managed at the Lawrence Berkeley National Laboratory in Berkeley, California. Another manager might have shrugged off the three quarters and even paid the bill with his own spare change. For Cliff, the $0.75 error — that was nine seconds of computer time — was the beginning of a trail that slowly led to a faceless hacker breaking into Cliff’s systems and, from there, breaking into computer systems around the United States.

Cuckoo’s Egg tells the story of Cliff Stoll’s strange and accidental turn to counterespionage. First suspecting a smart ass local high school kid or a prankster university student, the gravity of the situation slowly dawned on Cliff as the hacker continued his break-ins on a daily basis with the kid of drive, discipline and stamina that no student hacking on a whim would possess.

The FBI, CIA, NSA and Air Force all initially passed the buck when Cliff called alerting them to the hacker, unsure of jurisdiction, whether the crime was even worth pursing or how to even speak to one another.

“These were the facts of life in dealing with a bureaucracy: everyone wanted to know what we discovered, but nobody would take responsibility.”

This made Cliff, a liberal academic (described as “an ex-hippie, long hair, rumpled clothes, jeans, bicycles, sleeping under his desk”) at the famously leftist Berkeley, something very close to an intelligence agent — a spook, a spy — himself.

Much to the chagrin of his girlfriend Martha, Cliff spent weeks and then months sleeping in his lab, tracking the movements of the mysterious hacker. In the beginning, he wondered if the man on the other end was perhaps just another leftist from Berkeley with sympathetic goals. Martha expressed trepidation about his cooperating with so many black suit-wearing cops and state authority figures. Soon, however, it became clear that the hacker was not from Berkeley and was much less than sympathetic.

In an interview with C-Span, Stoll explained:

And what he was doing when he got into my computer was not reading my astronomy texts. He wasn’t reading about the structure of the galaxy and Orion. He wasn’t reading scientific things he was using my computer in Berkeley to search out over the computer networks to go into military computers. One after another after another. He’d break into military computers in Alabama and California in the Pentagon in Okinawa. He’d systemically reach out over the milnet — the computer network connecting military computers together — and into universities as well and try to break into them. When he’s succeed an break into a military computer he’d search. I would watch him. I watch him search for words like SDI like NORAD … systematically trying to get information about nuclear preparedness. And I’d watch him get information from a Pentagon computer about chemical and biological warfare plans for Central Europe.

Cuckoo’s Egg is more than just a supremely gripping tech thriller. It was one of the very first nonfiction tech thrillers. Published in 1989, there were worries that only 600 people in the world would ever care to read a book about a hacker breaking into various computer systems around the country, even if those systems were of importance to national security. There was little to no conception that computer security would become a topic of great interest for millions of people or that the book — even with the surprisingly lucid descriptions of Unix operating systems, international telecommunications systems and the occasional legalese — was transparently great. No one could fathom that Cuckoo’s Egg would help to inspire a new genre.

The New York Time’s 1989 review talks about some of the main characters in the book:

The central figures in ”The Cuckoo’s Egg” are the computer networks (like Internet, Tymnet and the Defense Data Network) themselves, data highways that carry millions of messages each day among computers all over the world – ”like a post office running at the speed of light.” Mr. Stoll and his fellow wizards see each network as ”a brain with neurons extending around the world.” These networks are programmed to adapt to changes in traffic volume and to failures in any of the thousands of on-line computers. On their own, the networks are able to create new communications paths and respond to requests for special services. As computers become smaller, faster and cheaper, networks are becoming pervasive – and merging, eventually to form a single global supernetwork. Networks can carry pictures, documents, software and a variety of other information. They can deliver messages almost instantaneously, so they lend themselves to conversations among almost any number of participants, conversations that can go on for weeks or even months. And networks can also be the theater of a worldwide information war.

In the fields of technology, hacking, law enforcement and even military history, Cuckoo’s Egg is an important read for anyone hoping to fully grasp the fundamentals of the war for information that has only greatly expanded into today.

The New York Times and insightful readers in 1989 saw Cuckoo’s Egg as a unique look at already-important communities and technology “that will play a major role in our future.” Now, as data transferred in bits and bytes continues to increase in importance, the book is still a prescient look forward as well as an invaluable look back. This is a classic worth reading today.

Check out Cuckoo’s Egg on Amazon.