In 1942, in Nazi-occupied Poland, a Jewish child was smuggled out of the Warsaw ghetto in a backpack. That child was Karen Kirsten's mother, but she knew nothing about this extraordinary event until one day a letter arrived from a stranger. After Karen eventually discovered the grandparents she loved dearly were in fact not her biological grandparents, she travelled the globe to uncover her family's past and to find the answers to baffling questions-why did her adoptive grandmother treat Karen's mother so unkindly? Why did she hide the truth that she was her mother's aunt? And why, if she appeared to dislike Karen's mother, did she risk her life to save her and bring her to Australia?