Richard Peck

In the boring desert of New Mexico, a single mother raises her two teenage daughters, Shade and Trudi, whose deepest desire is to leave the dead calm town. Shade is the type to escape in her extravagant fantasies while Trudi is so rebelious it could drive her away. (imdb)

Teenage girl is plagued by harassing phone calls. Her fear mounts when she's babysitting at a neighbor's home one evening and the caller rings her at that number. (imdb)