I've just finished re-reading the first three books of Dekker's "Circle" series. In the story a young man, Thomas Hunter, finds himself living in two worlds. Each time he sleeps and dreams he wakes up in the other world.
One world, is ours. And here, great evil is at work which could easily result in the death of most of earth's population.
The other world, is, in the beginning, a place where good and evil are divided and in which one can see with their eyes what is good and what is evil. The good side of the world is beautiful and the inhabitants enjoy close communion with their Creator. Their religion is called the Great Romance.
At first, it seems that Thomas is the only common link between the two worlds, but it becomes apparent that what happens in one is directly related to what happens in the other...with the fate of humanity hanging in the balance.
The series is Dekker's approach to the alligorical stories such as we see in the Chronicles of Narnia and the story of the Lord of the Ring.
The fourth book, Green, was written a few years after the series was published. I haven't read it yet, but it both fills in some blanks and advances the story somewhat.
I give the series a thumbs up - a good summer read!