I must say that this book is not what I expected though it keep me on my heels throughout the whole story. I love following along with the main character, Hartley, solving a crime that no one seems to see right under their nose.The plot line of this book left me giddy. Ms. Halliday did a great job creating a great mystery yet something accessible. I could see this plot really playing out in really life. Ms. Halliday gives the reader clues to piece by piece dragging them through the whole.The main character Hartley, is a girl I would love to be friends with. Loyal to the end, despite the betrayal she pretty much does anything she can to help. She's not one to leave them on their own but she made she they knew exactly where they stand. I love how she got help and snooped around.The whole motive of the story is good. I liked how Ms. Halliday unfolded it slowly before the readers eyes. I, myself, was dying to find out who the murder is. I tried to think but nothing came to mind. And when I finally found out, it made sense. Bravo, Ms. Halliday!If you want to solve a mystery, one depicted of purity and embarrassment, Deadly Cool will give you a great scandalous mystery to solve!