Tony (Ike Eisenmann) and Tia (Kim Richards) are other-worldly twins endowed with telekinesis. When their Uncle Bene drops them off in Los Angeles for an earthbound vacation, a display of their supernatural skill catches the eye of the nefarious Dr. Gannon (Christopher Lee) and his partner in crime, Letha (Bette Davis), who see rich possibilities in harnessing the children's gifts. They kidnap Tony, and Tia gives chase only to find Gannon is using her brother's powers against her.