Depths is a staggering novel. It's one of those books that sneaks into the lumber-room of your consciousness and entwines itself round whatever stuff you happen to keep in there.
Depths shares some of the qualities of Mankel's detective fiction. At the start of this novel, the protagonist, Lars Tobiasson-Svartman, appears to be a character not unlike Inspector Kurt Wallender - steadfast, disciplined, professional.
It is the start of the First World War. Sweden is non-aligned but worried about getting dragged into the conflict. Lars Tobiasson-Svartman is a hydrographer who has the job of carefully checking measurements of the depth of water in straits south of Stockholm.
From these unpromising beginnings, the prose builds an understated atmosphere. If you've read and enjoyed other Mankell novels, you'll recognise the stripped-back style.
The landscape is haunting (again, like the countryside in the Kurt Wallender books). In the case of Depths, most of the action takes place near an archipelago - and, in particular, on a single rocky outcrop, surrounded either by sea or ice. This setting becomes bewitching, unsettling.
The events that unfold in the course of the story are at once ordinary and brutally shocking. This is a novel that made me gasp out loud (which hasn't happened since I read Sarah Waters' Fingersmith, which is a totally different sort of book). You'll have to read it for yourself to find out why.
To summarise, this is a disturbing but completely gripping book. It reminded me most of Camus' L'Etranger (The Outsider) and various folk stories, but Depths is its own book - distinctive and haunting.