I was prepared to be disappointed reading the first chapter of this book but baring with it was worthwhile and it turned out to be a very good read indeed.
Thematically it is definitely a horror read, there are grisly deaths or horrendous injury at the end of each chapter to begin with and these chapters are not very long to begin with, it is also a brilliant time travel narrative but while the characters philosophise and try to analysis their circumstances it does not become too indepth. I would describe the time travel aspect as being more akin to fantasy fiction than science fiction, it is a case of magical or mystical transport and/or some kind of prehistoric, ancient, forgotten "technology".
There arent any answers about how this operates, or doesnt operate correctly as the case may be, there are hints in a dream sequence in which a character moves to a horizon and enters a stage he has just left that failing to figure out how to leave at this point will result in being repeatedly subjected to transport by unexplained forces. I thought this was great, similar to HG Wells' brilliant
The Time Machine (Penguin Classics), the process itself is mysterious to the reader but the point is to use time travel as a narrative tool, to present a human drama of individuals out of time and place.
Besides this I dont really consider that there are unfinished or unanswered aspects of the book. I kind of see it as a coherent and contained novel and it even finishes with "The End", while some aspects of the story, for instance one of the protagonists have five fingers rather than four fingers and a thumb or a grisly murder early in the story which is seemingly forgotten about but, perhaps on a second reading, these things make sense and relate to dialogue between the characters.
It is a human drama and character development is just brilliant, the protagonists are presented as entirely human, most of them are likeable, some tragic, others are despicable or at least selfish and arrogant but not without redeeming qualities altogether. The pace is great, it quickly develops into an action story with clear cut good and evil forces, the villains are one dimensional and wicked but it doesnt diminish the tale in anyway. The idea of refugees from other historical epoches invading more prosperous time lines was a little absurd and not really necessary but it can safely be overlooked as a piece of speculative dialogue which doesnt effect the overall story.
A great read which I'd recommend to fans of time travel, fantasy or horror fiction.