I received this book two weeks ago, and found it to be an interesting story. I liked Mila's character, and I liked the way Stella set out to figure out what happened to her. I also did enjoy how the ending was very unexpected. However, I personally found Ellie's character to be a bit annoying, though that may be because she was written as someone who was consistently in her sister's shadow. I also did think the book's pacing could have been a little better, with more on how they solved the murder rather than presenting that info in the last 150 pages. I did find the mention of the dark years and Stella's 'attack' on the other track runner to be very repetitive, because I felt like it was established early on how that affected their characters. Overall, however, this book was an interesting read. It's something that can be read in about two days (although it took me a lot more than that) and totally helps with getting out of reading slumps. It was also perfect for the back-to-school season. I will totally tell my friends to read this book whenever they want something suspenseful and quick.