If you're looking for a great police/investigative series then Line of Duty is for you.
It is one of my favorite shows from BBC One.
It's an internal affairs drama where a select group called AC 12 investigates alleged corruption within the police department all over England, but it morphs into something much greater than a typical undercover sting operation.
The first season starred the great Lennie James, which laid the groundwork for a serialized story that runs alongside the case at hand throughout the series. Mercurio continued to add superstars to its roster like Keeley Hawes, Thandie Newton, Kelly Macdonald, and Stephen Graham.
Season one has just begun airing on AMC, and each season gets better and better. You can see all five seasons so far on Amazon Prime and Acorn. Season six will air sometime this year, hopefully.
Seasons 3&4 are streaming on Hulu.
It's the brainchild of Jed Mercurio, who's stand-alone series Bodyguard was a big hit on Netflix in the U.S. The show was Emmy nominated and won a Golden Glove for Richard Madden.
The Guardian's Rebecca Nicholson writes:
Jed Mercurio’s breathlessly tense thriller has torn up the rulebook on what police procedurals can and should look like. Its shock-horror twists, gasp-inducing cliffhangers and willingness to bump off any character at any moment have turned it into one of television’s most gripping blockbusters.
It has some of the best interrogation scenes ever filmed for television since Homicide, Life on the Street
This is a continuation of our Quaranstream series.