Isn't the cover just bizarre and spooky?? I know, it's awesome. ;)Mackie Doyle isn't like other teens in Gentry. He can't stand to be in a car, he can't be inside a church, and he gets sick when he smells blood. Not human, Mackie is instead a Replacement, a creature who was left in a human baby's crib 16 years ago, a creature from the dark world full of death and magic and horror that is hidden under Gentry. His allergies to consecrated ground, iron, and blood are slowly killing him when he wants desperately to live. When another baby goes missing and is replaced by something dark and horrifying, Mackie is pulled back into the world he came from, the world under the Slag Heap, the world known as Mayhem ruled by a frightening little girl called the Morrigan.Haunting and chilling, this book has a way of getting under your skin, revealing the horrors that people turn their backs on. Gentry is dying, filled with people who ignore what's strange and different. Mackie's own parents know what he is, know that their son was stolen from them and replaced by this frail creature, but they moved on with their life. The same can't be said for Tate, a girl whose own baby sister was taken and replaced. Her brutal and honest attitude, her take no crap and find the answers take on life fuels her anger, as well as her need for Mackie to head into the other world to find out what happened.Contrary to Gentry, the world of Mayhem is thriving, inhabited by walking, rotting dead girls and otherworldly creatures. Mackie's return to them is nothing short of a miracle, even when he walks right into a decades old war between the Morrigan and her sister, a far more evil and dangerous creature.Mackie as a character was genius. He was tortured, by his allergies, by his human family (maybe not Emma, she still loves him), by his 'actual' family. He's also so strong, braving the dark worlds of Mayhem and Misery to find Tate's sister and confront the darkest side of the secret world below Gentry.The Replacement is one of those books that slips quietly into your brain and works its way under your skin. So haunting but so beautiful, so full of dark secrets, dark creatures, dark memories, and the desire to survive and find a place to belong.