The Cuckoo’s Egg by Cliff Stoll tells the story of an astronomer who discovered a slight irregularity in their computer system when he became a systems manager in the 1980s. Out of curiosity, and maybe boredom, he chose to investigate it and ended up tracking a cyber spy for about a year. He details the ways he devised to track the spy without being detected and the various creative routes the hacker used to accomplish his goal. Before it was resolved, the military, FBI, CIA, and others were all involved and watching his progress.
Fascinating Read!