The Iron Chariot

Voted #1 in a poll of the greatest Norwegian crime novels of all time
On a blazing hot summer's day, holidaymakers at a guesthouse on a Norwegian island are shocked to discover a fellow guest has been found murdered out on a desolate plain. The nameless narrator, an author, was the last person to see the victim alive; shortly afterwards, he was disturbed by a noise like 'a rattling of chains'. A local tells him this is 'the iron chariot', which is said to presage death.
Drawn unwillingly into the investigation, the narrator is puzzled by an enigmatic detective's apparent inaction, and troubled by unfolding events. These begin to take a toll on his mental wellbeing and he sinks into a state of dread, exacerbated by mysterious happenings at the cabin where he is staying.
So profound is his unease that he feels he must leave the island. Then Krag promises to tell him the solution to the mystery…