Reacher is an itinerant, homeless enormously strong individual with an inflexible personal code of ethics. In each series he visits a new town with a new ensemble of locals. And new villains that need straightening out (exterminating). There are some ancillary characters that show up in more than one series. The emphasis is upon bulldozing through obstacles like superman and impressing folks that don't realize his abilities. Occasional quips lighten things up at times, but clearly Reacher is not a big talker, and he fixes most issues by knock outs or shoot outs. Moral ambiguity arises very seldom and is limited to uncertainty over priorities. Which comes first if his goals compete for attention? Is it saving the good guys or bashing the bad guys. Although the choice can go either way, sometimes the good guys are not saved, but the bad guys definitely end up dead.