If you want to know the difference between American crime series and English crime series watch Line of Duty. It is like comparing a fine red wine and a bottle of cheap moonshine whiskey. You will taste the difference.
This English series revolves around a group of British anti-corruption police officers in a unit called AC-12. They work relentlessly and smartly to seek out corruption among fellow police officers. So they are frequently unpopular with their fellows. The British series is done without all the “pretty people,” as a friend of mine once said. It has real people instead. People with warts. Nasty people; good people and always some people with a lot of good and bad. The cases are never simple. They never follow tired formulas. The series is filled with surprises. Take nothing for granted. Expect a ride. Rather don’t expect anything. Just enjoy. Like a very fine wine.