One of the biggest mysteries surrounding the French Revolution and the resulting Reign of Terror was what actually happened to Louis-Charles (also referred to as King Louis XVII), the dauphin of France. Donnelly masterfully uses that mystery as a backdrop for this modern tale that weaves historical fiction with a modern teen "problem" novel.

Andi Alpers' family has totally crumpled. Her mother is barely holding on to her sanity, disappearing into her paintings. Andi's father fled into his career as a geneticist. The family was shattered when Andi's younger brother was killed in a mysterious car accident months earlier.

Andi herself seems to be barely holding on with the help of qwellers, an anti-depressant, and that seems to be doing little to help with her schoolwork. She is on the verge of failing out of her private prep school, and she has barely done anything with her senior project. She has chosen the topic, an obscure French Revolution era composer, but that is about it.

When her school's dean reaches out to her father to tell him about her scholastic status, he comes home and takes Andi to join him on her Christmas break. He is currently in Paris working on a project to identify whether a preserved heart that was allegedly belonged to Louis-Charles truly belonged to the dauphin. His genetic expertise should allow him to do just that by comparing DNA taken from the tiny heart to a tress of hair that once belonged to Louis-Charles' mother, Marie-Antoinette. Andi begrudgingly agrees.

Upon her arrival, Andi is given a gift: a guitar from the French Revolution period. While fiddling with the case, she runs across a secret diary ... one written by Alexandrine (usually referred to as Alex), who was a poor actress/puppeteer taken into the royal household to be the companion to Louis-Charles.

Andi, whose continues to skirt with thoughts of suicide, finds herself being drawn deeper and deeper into the Reign of Terror as she researches her senior thesis with primary documents at Paris libraries and the musicians home and the backdrop of what she is reading in Alex's diary. In Alex, she finds parallels in the suffering she and her family has confronted with the loss of her brother as Alex must watch her beloved ward be taken into custody and held prisoner by the various revolutionaries.

All the while, she also finds herself rebuilding her shattered life through her interactions with the people she meets in Paris, both current and historical figures.

I ended up reading this one as a possible nominee for the 2012 RI Teen Book Award. It has been the best one that I have read, though, I do have to admit that some teens might be put off a bit by the length. I am also not sure that they would be drawn to the French Revolution, but I do think the book could really be sold on Andi's angst and the troubles with which she and her family are confronted. There are tons of great references to today's music, and it's parallels to the classics, lots of action for Alex and her exploits as a counter-revolutionary, and same amazing characterizations and writing that really bring Alex and Andi to life.