Person of Interest is an American sci-fi crime drama television series created by Jonathan Nolan. The series is about John Reese (Jim Caviezel), a former CIA officer who is recruited by Harold Finch (Michael Emerson), a mysterious billionaire, to prevent violent crimes in New York City.
You are being watched. The government has a secret system: a machine that spies on you every hour of every day. I know, because I built it. I designed the machine to detect acts of terror, but it sees everything. Violent crimes involving ordinary people; people like you. Crimes the government considered 'irrelevant'. They wouldn't act, so I decided I would. But I needed a partner, someone with the skills to intervene. Hunted by the authorities, we work in secret. You'll never find us, but victim or perpetrator, if your number's up... we'll find you
- Harold Finch narrating the season 1 introduction
From Person of Interest on Wikipedia.