I just finished this book and the ending really took me by surprise. It was a good book. Not totally what I was expecting because the setting is WWII time frame but the war wasn't a huge part of the story. I had a little trouble with the layout of the book and how the story was told in bits, but then at the end, it all made sense. A really good read that is worth your time. I can't say too much about it without giving something away. So, just read for yourself and be the judge.
Summary from amazon.com:
During a picnic at her family’s farm in the English countryside, sixteen-year-old Laurel Nicolson witnesses a shocking crime, a crime that challenges everything she knows about her adored mother, Dorothy. Now, fifty years later, Laurel and her sisters are meeting at the farm to celebrate Dorothy’s ninetieth birthday. Realizing that this is her last chance to discover the truth about that long-ago day, Laurel searches for answers that can only be found in Dorothy’s past. Clue by clue, she traces a secret history of three strangers from vastly different worlds thrown together in war-torn London—Dorothy, Vivien, and Jimmy—whose lives are forever after entwined. A gripping story of deception and passion, The Secret Keeper will keep you enthralled to the last page.