Book Review: Sarah's Key

I have a hard time stopping reading a book I don't like, and I don't know if this is a good quality or a bad one. Does it mean I am stubborn and refuse to give up--or that I am optimistic and keep hoping the book will redeem itself? Or is it a mix of both? I have a stack of books to read: it's not like there aren't more options, but for some reason, I persist--even when I am not enthralled with the book. Such was the case with Sarah's Key by Tatiana de Rosnay.
I had heard good things about it, and the blurb on the back looked promising. And I must admit: the first 100 pages were great, actually. I like a novel that alternates between past and present, as this one does. Let me explain the premise:
In 1942, 10 year old Sarah is taken with her parents from their home in Paris. Before she leaves, she locks her young brother in the secret cupboard in their bedroom, promising him that she'll be home soon, never suspecting that she will not. Thousands of Jews--mostly women and children--are detained in a bus station in the city for days without adequate food or water or bathroom facilities. When Sarah shows her parents the key and explains that she locked little Michel into the secret cupboard, they are horrified, and Sarah quickly realizes that she has doomed her brother to a horrific fate. From the bus station, which is called the Vel' d'Hiv, they are taken to an internment camp near Orleans, and soon Sarah is separated from her parents, who are taken to Auschwitz. Sarah's story continues on, though, as she is tormented by her brother's fate--for which she blames herself completely.
In 2002, an American woman, a journalist living in France, is assigned to report on the 60th anniversary of the Vel' d'Hiv roundup, something that she--and most people in France or elsewhere--know little about. Julia is appalled to learn that this operation was carried out by French policeman under German orders. As she learns about the inhumanity of the treatment of the prisoners, she feels personally affected and soon becomes caught up in the story. By tracing the clues and talking with witnesses, she learns that the apartment her husband is renovating--the one his father had lived in as a child--was Sarah's home. Many past secrets, long buried, are revealed as Julia keeps digging.
Doesn't this all sound good? It is a great idea for a novel and an important piece of history that deserves to be told. I have no problem with any of this. For the first 150 pages or so, the brief chapters alternate between Sarah's story and Julia's. Then, midway through the book, Sarah's story reaches a climax and ends. The rest of the novel is Julia's story alone. The chapters are short and often fast-paced, and indeed the novel itself is a fast read.
I guess the part that annoyed me about the novel is the fact that Julia's character was so much less interesting than Sarah's, and Sarah's story ended so precipitously. I felt there were other paths the author could have taken with the plot, paths that would have been more satisfying and less predictable. The ending was too obvious, and yet the motivations of the characters when they got to the end weren't entirely believable. The last thirty pages skipped three years into the future, and all of Julia's problems from the rest of the story were summed up and swept under the rug. I actually rolled my eyes a few times in the last scene!
Normally, I consider myself a pretty tolerant reader, but this novel had the potential to be so much more, and I thought the pace, the character development, and the plot did not live up to it. I would have liked to see more mystery, stronger characters, fewer loose ends with minor characters, and (please) longer, more complex sentences.
Apparently, there is a film version of the book, and I plan to see it. It will be interesting to see how the film makers handle the story. I'm looking forward, however, to my next book. I hope it far surpasses this one.