This is a two-character dynamic that frequently shows up in fiction. Somewhere in the Backstory, two male friends are making their way in the world as Those Two Bad Guys, keeping up the Masquerade for the Ancient Conspiracy, going to war for The Empire or doing hits for The Syndicate. One day, orders come down from the top to Shoot the Dog. The "Outside" man pulls a Heel Face Turn and refuses to go along with it. They may have fallen In Love with the Mark, had his training wear off, or decided Even Evil Has Standards. May overlap with Red Oni, Blue Oni. Compare Internal Reformist.