Goro Koyama, 50, is a private investigator and founder of Japan PI, a bilingual investigation agency based in Tokyo. His agency covers everything from legal and business investigations to finding missing persons, and specializes in working with overseas clients.

1. How did you get into private investigating? When I was young, I wanted to be a writer. I thought that if I got involved in some sleazy jobs, like private investigation, then I would get a lot of inspiration to write about.

2. What did you study at college? Ancient history. I was also a member of the full-contact martial arts team.