Aimee Leduc, a young French-American detective living in Paris, is hired by a renowned Holocaust survivor to decode an encrypted message and ends up entangled in a murder investigation in the Marais district of Paris. Her undercover search leads to a neo-Nazi group and lots of intrigue involving current politicians and people involved in the German occupation of France in World War II.The story was interesting and the characters certainly were a challenge as many were not who they seemed or presented themselves to be. Aimee Leduc was certainly resourceful and extraordinarily skilled at not only investigating the case but in taking care of herself. She's an enigma that this story seemed to only scratch the surface of and I very much liked her personally and as a detective.Where this story fell short for me was with the lack of depth in developing the secondary characters who are a constant in Aimee's world. It was obvious that these were longstanding relationships but we weren't given enough history to make sense of their roles, especially Inspector Morbier. I couldn't discern if he had a fatherly, antagonistic or lust-from-afar relationship with Aimee. Her partner, Rene, obviously has a backstory but was relegated to pitching in here and there in a confusing way. Aimee's connection to Yves ended up being just bizarre in my opinion.There was also a lot going on in the story. I didn't have a hard time tracking it but the transitions were awkward. I also felt a bit let down by the ending as there were so many issues that felt unresolved. I like the character so I'm committed to reading at least one more book in the series and hope that this first book bore the pains of establishing the foundation for the rest series.