Altered is a seriously impressive debut novel from Jennifer Rush. Full of mystery, suspense, romance, and betrayal, this book has it all. The characters were both the best and the worst part about Altered. Truly it's the only complaint I have about this book. The boys were fabulous and I'll get to them in more detail in a second but Anna had a few flaws that really got on my nerves. The biggest one was her obsession with Sam. All she could think about, even in a life-threatening situation was him. I get that she's had a crush on the guy for years but crushing and obsessing are two very different things and Anna was definitely on the obsessive side. Other than that though I thought she was pretty kick-ass. She might seem meek at the beginning but she definitely comes out of her shell throughout the book and I loved her after seeing her more bad-ass side. The guys were the best part of this book, at least to me. Each boy had a very unique personality and it never got confusing with them. I think the best part about the boys was that they weren't perfect. Each boy had his own flaws. Nick was very surly. Cas was a huge goofball who very rarely took things seriously, even when he should. Trev had quite a few secrets. As for Sam, he was kind of a jerk at times. I know he didn't mean to be but he truly did come off that way. Whereas I normally wouldn't like that in a love interest, it gave him a bit more depth. And he was never a jerk in an abusive way. The guys definitely made me love this book as much as I did.The relationships between the characters were so dynamic. The boys interacted with each other very differently. Sam was clearly the leader but that didn't mean his authority wasn't questioned. Sam and Nick were always at each other's throats. Sam and Cas, on the other hand, were always joking around. Trev wasn't really close to the boys but he was best friends with Anna and he was always there for her. Nick hated Anna and he never stopped letting her know. As for Anna and Sam, they had such an odd relationship. There was always so much tension between them and I just wanted to shove them together and make them kiss. While they both clearly had feelings for each other, they didn't rush right into them and do something stupid while they were on the run for their lives. I loved that about them. The story is just plain awesome. It starts off a little slow, giving the reader background information and really setting things up. However, it very quickly takes off and it never slows down after that. Anna and the guys are on the run and they are never safe. As they look for glues regarding Sam's past they start to realize that they are a lot more clueless than they originally thought and that somehow Anna is all tangled up in everything. I can normally predict what's going to happen in books but that was not the case with this one. There were so many things that shocked me. I was truly kept guessing until the very end.Overall, Altered is a must-read for pretty much all YA fans. It has something for everyone and I think everyone will really enjoy it. This may be her debut novel but Jennifer Rush has already made a fan of me.