The two main characters are Sarah and Julia. Sarah's story is the heart of the narrative as it unfolds her experiences during a very difficult time in history. Julia, on the other hand, is the modern - day character. She is a journalist or writer (depending on the version). Her inquisitiveness about Sarah's past forms the other part of the story, and their two stories are intertwined as the plot progresses.
Sarah is the central figure. She endures a great deal during the roundup. And then there's Julia. Julia is sort of on a journey of discovery. She stumbles upon Sarah's story and becomes deeply involved in learning more about it. There may be other minor characters as well, but Sarah and Julia are the ones that drive the story forward.