It is the future, a hundred years from now, when a strange new bird is glimpsed in a tree. A girl and two boys track down where it came from - the secret corridor - and danger is everywhere around them.
Librarian note: There is more than one author in the GoodReads database with this name
John Gordon was an English writer of adolescent supernatural fiction. He was the author of fifteen fantasy novels (including The Giant Under The Snow), four short story collections, over fifty short stories, and a teenage memoir. For more information, please see http://en.wikipedia.org/wiki/John_Gor...
At a guess, I'd say this chapter book was written for children 6-8. It's a science fiction thriller, written in 1990 and set in 2090. Nothing special here, nothing durable for today's reader. Even the Gordon "completist" who wants to see everything John Gordon wrote will find this difficult going, though it may take only 30 to 60 minutes to read.