From IMDB:

When a seemingly perfect and happy family is murdered by someone they knew and trusted, cracks appear on the surface of a supposedly idyllic community.

CORRECTED REVIEW: Now there are all 4 episodes.

From Acorn TV you can stream the 4 episodes of this Scottish detective series. Each episode lasts about 45 minutes.

Rather than classify this series as a detective series, instead be aware that this story is a real tragedy in the classic sense that everyone in the story suffers.  In other words expect a bitter tasting ending.

David Tennant plays the lead tragic figure Tom Kendrick.  Tennant has an impressively long acting resumé including playing D.I. Alex Hardy in Broadchurch (which is a “must see”).  His character Tom is a remarkable contrast to that of D.I. Alex Hardy.

As the story progresses, you will see that first impressions are deceiving.  Little by little we discover the real nature of several inhabitants of this small town.

Superbly well done, but brace yourself.