Well that was a stunning conclusion to an incredible series. I did see some of it coming but was still intrigued to find out how it would be pulled together.
Mercy and Xavier are in love but won't admit it to each other. Typical right. Anyway, they go through hell and back to get to where a future may be possible. With all the twists and turns it could go either way, and with the "The Watchman" involved, there's no telling who will survive.
I highly recommend this thriller conclusion to an fabulous series. Do yourself a favour and read them in order. They could be read separately but makes more sense in sequence.