This is an extaordinary imginative achievement. Hannah Kent gives herself an obscure historical and geographical setting - Northern Iceland in the 1820s - which she has had to thoroughly research, places in it a tale of passion, murder and punishment which is based on a real history - and then manages to turn everything into a compelling, tragic narrative.
It reminded me of the Thomas Hardy which used to reduce me, as a teenager, to emotional blubber. As Agnes narrates her life and, eventually, the crime for which she will be beheaded - at the same time becoming the last person to be executed in Iceland - we know that this is how the story will end, however much we might wish it otherwise. And as the story unfolds, we wish it even more. That is part of Hannah Kent's achievement.
Another part is the cast of supporting characters, two of whom - the man and then the woman who listen to Agnes' narrative - undergo their own spiritual transformation as her tale unfolds.
It is incredibly well done and I recommend it very highly.