Shadow Zone is a series of 13 children's horror fiction books written in the 1990s by several authors using the pen name J. R. Black.
A child or a few children meet a monster who asks for help and usually threatens them or their family.
Aggressive at the beginning, they may finally be nice or touching.
Two of the books, The Undead Express and My Teacher Ate My Homework, have been made into films.
Other children's horror series from the 1990s include Are You Afraid of the Dark?, Bone Chillers, Deadtime Stories, Shivers, Spinetinglers, Spooksville and Graveyard School.