Fascinating story detailing how Brian Krebs, an investigative journalist and security expert uncovered the identity of a notorious cybercriminal. Although some technical investigation is involved, it's interesting to note that most breakthroughs were due to good old fashioned detective work, and following the money.
https://krebsonsecurity.com/2017/01/who-is-anna-senpai-the-mirai-worm-author/