The Blackhouse sells itself as a detective procedural and it sort of is. There is a body and there is a policeman. But this is almost an incidental framing device. The real story is the back story - Fin Macleod's childhood on the Isle of Lewis. The murder investigation is just a vehicle to allow the various secrets to be revealed.
And this is where Peter May demonstrates great insight into the island psyche. The popular misconception is that because people know one another, they have no privacy and no secrets. In fact, the opposite is true. Although islanders - at least on Lewis - don't all know one another, they do tend to bump into the people they do know quite often. There's nowhere to hide, and that means people guard their privacy very closely. Everyone has secrets and people learn to hold their tongues.
Thus, as Fin Macleod returns to his native Lewis after 18 years away, he finds people very closed and reticent. Even his childhood friends seem to give him a wide berth. There is certainly no hint of a fatted calf being slaughtered. Instead, it is more a case of Fin finding ghosts from the past. We have stories of his first fumbled kiss as an 8 year old in a hayloft; the expedition to scale the roof of Lews Castle to spy on bathing beauties; the place on the annual guga hunt on Sula Sgeir.
As an aside, there was a book written about the guga hunt (The Guga Hunters) by Lewis poet Donald Murray. This is a name of a character in The Blackhouse, and I doubt that this is coincidental. And on the subject of names, many of them are Gàidhlig and only a couple are spelt out in terms of pronunciation. I imagine much puzzlement amongst non Gàidhlig speakers at the likes of Seoras, Seonaidh and the farm at Mealanais.
Peter May's writing is evocative, and although Crobost is invented (I took it to be an amalgam of Cross, Swainbost and Harbost), the novel is otherwise faithful to the geography of Lewis. It is this sense of place that lifts The Blackhouse into something very special. There is the beauty and the bleakness; there is the loyalty with the undercurrent of menace.
The slow pace allows for the development of character and it is to Peter May's credit that he does not fall into lazy stereotypes. The people of the island are shades of grey - nobody is all good and nobody is all bad. They have different takes on the same situation; they act in consistent but surprising ways.
The novel has a slight failing in that the ending, when it comes, has to resolve the murder. It does this in a slightly far-fetched, melodramatic way. It's a shame when the rest of the novel is so realistic and measured, but I suppose it is the price that must be paid for having used a murder as the framing device.
I would recommend the novel to anyone who wants to learn about life on Lewis or the island psyche. As a thriller or whodunit, it will probably fail to deliver and frustrate with the meandering digressions into back story.