Tony and Tia are orphaned teenagers who have paranormal abilities. Tony possesses the ability of telekinesis, which he can access most readily through playing music, particularly his harmonica. Tia's strengths include the ability to unlock any door by touch and communicate with animals. Both siblings can communicate via ultrasonic speech audible only to each other, but Tia cannot speak normally and is regarded as strange because of this. It is later revealed that Tia is not unusual in this respect, but Tony is; few of their kind have the ability to speak out loud. After their foster guardian Mrs. Malone dies, they are placed by social services in a juvenile detention home under grim, unwholesome conditions, where Tia befriends a black cat named Winnie.