After a lifetime in law enforcement, I don't like cop shows. The vast majority of them take themselves waaaay too seriously, and Hollywood displays very little understanding of how cops and police departments work. Oh, they have their technical advisors who show them how cops do tactical stuff, and they do manage to get that stuff mostly right, but it's the day to day stuff that they screw up. For example, how many times have shows depicted a detective leaving some major department and going to another city and immediately becoming a detective? Sorry folks, it just doesn't work that way. I don't care if you have a gold shield in the Big Apple, it you move to another state, you're going to go through the entire testing process all over again, go through another academy, and start out as a junior patrol cop working a beat.
So I don't like cop shows. Except.....
Mary Shannon has to be the most irascible, sarcastic, cynical, wry, blunt pretend LEO to ever pin on a TV badge. I love every minute she and Marshall are on the screen. Whoever writes for the show, especially the dialogue, is a genius. Practically every other line Mary utters is something that I wish I had thought of. At the same time, I identify with both her partner Marshall, and her supervisor Stan. Mary is the sort of partner and subordinate that you love to work with while simultaneously dreading whatever they're going to do next.
The show is hardly a model of realism, but I've given up on Hollywood ever getting that right. I watch the show because I want to see Mary cause Stan to pull out the rest of his hair, to hear her lay into some pompous FBI agent, to tell some protectee or family member just what an idiot they are, or to cause Marshall to go off on some existential tangent. You go girl!!