The agent has worked 'undercover' in several countries.
He went 'undercover' as a drug dealer.
an 'undercover' investigation
(..) my network-- Craigslist, Let's say we get lucky, I mean, incredibly lucky, and find a guy who's not an undercover cop or some kind of survivalist nut-job wannabe. You gotta ask yourself-- How good is good enough? Because whatever goomba we buy (..)2011 TvShow: Breaking Bad Title: Problem Dog Season: 4 Episode 7