It’s interesting to see and compare this with the other European police procedurals/mysteries that I have recently watched. This one is not nearly as bleakly dark as seems to always characterise the original Nordic Noir but like them the personal relationships between the investigators their personal lives and the mystery are all effectively connected. In this one, to be honest, not as richly as in many I have seen but still effective. I like the use of the central character running at the start, and sometimes at the finish, of each episode which gives a subtle sense of his obsessive nature - an element that I think is needed for the effective TV detective.
On a more personal level I much enjoyed the Welshness of it (well, to be accurate, North Wales and particularly Aberystwyth) with that wonderfully characteristic scenery at once bleak and appealing.
I have only seen the first two so far and will continue - although whether for all three series - as the personal/family background of the main character is clearly going to be of importance. It has been very effectively and subtly brought in from the start (separated from wife and unable to see his daughters). And there is also the reason why he, from London, has been moved to rural Wales. There was a brief hint in the second story about why (punishment?) but no more - quite an effective hook to keep one watching.
Low-key and less flamboyant, as suggested above, compared with European but no the less effective for that.