The story centers around the passengers of a ship bound for America in the 1840s - one of the coffin ships associated with Ireland during the Famine. They are connected in various ways and the book goes back in time to tell us about how each of the characters got to be on the same ship at the same time. And it all comes together really well in the end.
It paints a horrifying picture of what life in West Ireland must have been like at that time. I think that's what struck me the most. And my brain simply can't comprehend how terrible it all was, while at the same time knowing that there wasn't a famine at all, there was plenty of food for everyone, it's just the potato crop that failed and there was nothing else available to the poor Irish people. Unthinkable.
I'd been saving this book for when I actually go to Ireland again and I'm really glad I did. We travelled all over the Western coast, inluding in Irish-speaking Connemara, so the place names mentioned in the book were all familiar to me. That was pretty cool.
I think that everyone interested in European history should read this. American history too I guess, since the Irish poor who didn't die emigrated to the US. Don't miss this, it's really worth reading. The story and the characters really stay with you - I'm already looking for other books set during the same time period because I want to know more!