Shift (review)

After her parents' divorce and her own attempted suicide, Olive is back at school, but she's no longer the plastic popular girl she once was. Now she's what her former friend Katie calls a "road accident"—angry, standoffish, and overweight, with a snarky new best friend, Ami, who stands by her no matter what. Enter Miranda Vaile, a new girl who comes dragging a bad reputation. Olive and Ami think there's something off about Miranda, especially the way she obsessively watches and imitates Katie. Soon, Miranda and Katie are best friends, but it seems that the more Miranda comes out of her shell, the more Katie retreats into one; in fact, Katie seems to be shriveling to the same degree that Miranda sparkles. Olive and Ami become convinced that Miranda is a shapeshifter—a parasite that literally drains the life out of her host. When Katie dies as a result of anorexia, Miranda needs a new host, and despite Ami's warning, it appears that Olive will be her next victim. The subtle but persistent horror of this story resides in Miranda's inexorable charm set against Olive's painfully rendered vulnerability; she's cut herself off from everyone who might help her, including a boy who shows both an interest and a willingness to believe that Miranda might not be fully human. Because Olive is revealed to be an unreliable narrator, Miranda remains an unresolved enigma, but whether she's a paranormal being or simply a toxic seductress, her creep factor is undeniable. Readers with a taste for psychological tension that simmers just below the boiling point will nibble their nails all the way through this Australian import.