One of Us: A whodunit that wonders, what would I do?

The Elliott and Douglas families are left reeling when they discover they have both lost a child in One of US (BBC One, Tuesdays, 9pm).

Childhood sweethearts Grace Douglas and Adam Elliott grew up as neighbours somewhere in rural Scotland. They fell in love, got married, got pregnant (not in that order) and moved to Edinburgh. When their blood-drenched bodies are found in their flat, a domino topples and everything starts to fall down around the two families.

It's a modern murder mystery, but One of Us has elements of classic Agatha Christie whodunit (especially Ten Little Indians). Our players are brought together by an usual event, a mysterious stranger arrives, and soon the body count starts to rise and skeletons start falling out of closets left, right and centre.

Our usual suspects include nurse Claire (Joanne Vanderham) shattered by her brother's death; but who's this mysterious ex-boyfriend of hers? John Lynch is well cast as stern Scottish dad Bill, and Julia Stevenson is excellent as Grace's grieving mother Louise, who is battling unsuccessfully to stay off the bottle. There's a taciturn farm hand, and moody, introverted teenager Jamie Douglas, who is infatuated with Claire.

Remote locations have a history of making for great freaky settings (Twin Peaks, Top of the Lake, The Blair Witch Project) and Scotland should take a bow for its brutal and beautiful role here too.

Written by the same brothers who brought us The Missing, Jack and Harry Williams say they set out with the goal of getting the audience to empathise, to put themselves in the characters' shoes, and to leave them with more to think aboutthan what's on the telly next.

In episode one, they do just that. Questions about morality, family and the lies people tell are asked. And the final scene leaves you wondering, what would I do?

One of Us is at times let down by some soap opera-style acting (particularly from Joe Dempsie as Rob and his girlfriend Anna played by Georgina Campbell) but their characters have yet to get much screentime, And the introduction of the wonderful Ade Edmondson as Grace's estranged dad at the end introduces another tasty red herring for episode two.