Jack just lost both of his parents, it's the great depression, and he's not quite sure what to do. Then, Jane and Tony show up and the three leave on a journey to find something better than what they're leaving behind and run into gangsters, some new friends, and a lot of adventure along the way.
Andi has lost her brother, watched her mom lose it, and is about to be expelled. Alexandrine lived two centuries ago and is caught up trying to save a young prince during the French Revolution. The two are on a collision course with each other when Andi finds Alexandrine's diary.
A student recommended it, I read it, and it's some of the best written YA lit I've seen. It takes itself a touch too seriously at times, but it's still rattling around in my brain weeks later.