This was a 3.5 for me. I don't know, but I just had a hard time understanding the chemistry between Hawke and Sienna. I preferred Lucas and Sascha's story/chemistry better. I guess i had a hard time understanding Sienna's predicament. I couldn't quite buy into how mature she is at the age of 19. Given that most of the characters in the book have had to go through a lot when they were younger. Anyhow, Walker and Lara's story were a fabulous addition.