This novel was entirely composed by letters, except at the very end when we read the journal of one of the side characters. The letters offer a beautiful detailed way of writing between the characters. They also eliminate the narrator, to an extent, as the story slowly unravels over a number of letters. The writers also write differently to each other, depending on their friendship or otherwise. The letters are also very personal, and always written in the first person from the view of the writer.
Like the last book I read, The Slap, this novel has such unique and distinct characters. They jump off the pages and are absolutely real.
Ultimately, the story is a love story. It follows a similar structure to other love stories - complications between the lovers coming together, and the love being obvious to the reader but not to anyone else. The lovers finally get together at the end, though I found the ending a bit of an anti-climax. I knew that they would get together in the end, but the end failed to give me the emotional elation that I was expecting. The letters worked well throughout the story, until the ending, for this reason. There wasn't enough detail at the end to build the emotions of the reader.
The story is also about the occupation of Guernsey during World War II, and the writer, Juliet, researching this for a topic of her new novel. There are some tragic stories that are told to Juliet, through letters from the people of Guernsey. This is another reason why it's good that the story is written in letters, because you can put it down after each letter, if they get too much.
This book was also very inspiring to me, because it's written from the point of view of an author corresponding with her publisher. It's also about the author finding a new idea, writing, editing, and submitting for publishing. Obviously the process is very different these days, and also different because the author's publisher is the author's best friend (which helps).
To quote one of the characters in the story: "Reading good books ruins you for enjoying bad ones".
I highly recommend The Guernsey Literary and Potato Peel Pie Society.