Everyone knows the Y chromosome carries with it the instinctive urge to lie under pressure. 
 Which, incidentally, was what Josh was going to be under when I found him. Serious pressure. 
 On his larynx. 
 (p 11) 
 Deadly Cool is a quick, fast, funny read. I've always loved teenage sleuth books and their inadvertent discoveries, mishaps and unusual ways they solve crimes. 
 Hartley is a character that you just have to like. She's funny (her inner monologue in the book is one of the funniest I've ever read), sweet, caring, curious and opinionated. You can't help but like her. Sam is the ultimate best friend. Who else would help you break into your boyfriends house? 
 The mystery was ok. There wasn't too much too it. I was surprised by who the killer was. The killer, and the killer's motives, made me laugh at the ridiculousness of it (not really realistic, but funny). This is one of a few books that I didn't really care what was happening in the plot because the characters were written so good. The plot wasn't bad or anything, I was just more invested in Hartley, Sam and Chase than I was in the mystery. 
 I'm looking forward to reading Hartley's next adventure, Social Suicide.