If Lizzie thinks her little brother Matt can't get any freakier, she's about to learn she is way wrong. When Lizzie and Matt suddenly switch bodies, Lizzie starts to see how warped her little brother's world really is-firsthand! Meanwhile, Matt's gotten into Lizzie's head (literally!) And he's causing all sorts of trouble as his own big sister! How will Lizzie get back into her own body, and out of this nightmare! Plus, in Part Two, weird things start to happen at the Hillridge Junior High Halloween dance!