Spoilers
I wasn't all that blown away by the first book, it was a decent enough read but it felt more like an overly long introduction/set up rather than a story within itself… Because of that I thought there would be a few books which would slowly build up to a big finale. I was surprised to find that Falling Light was the last book and that the series was just a duology. I didn't think the story could be dealt with in one book in a satisfying way. Thankfully, the plot and characters were all wrapped up relatively nice and neatly.
-Most of the first half was spent on Mary and Michael trying to reach their ally/friend/mentor, Astra, whilst avoiding the Deceiver (the bad guy), his minions, and the authorities. Them running around and occasionally fighting one of the bad guys wasn't all that interesting, it didn't really add anything relevant to the overarching plot or characters. It was only in the latter half when Mary and Michael reached Astra where things started to get more exciting, the plan to destroy the Deceiver came together and it made for gripping reading.
-Mary and Michael were more or less decent characters, they both irritated me at times though. Michael was too closed off and pushed Mary away whenever he was upset, and Mary was too do goody and moral about things when she didn't have the luxury to be like that.
-It was annoying how Mary kept pissing around and delaying the race to get to Astra. Hers and Michael's life was in danger and instead of rushing to safety and help she kept wasting time with nonsense even though she knew that the bad guys were right behind them. She was a very frustrating character.
-I liked Astra a lot more than Mary, she talked more sense and was willing to make sacrifices to ensure the Deceiver and his evul plans would die. Astra had her priorities right whereas Mary ignored the bigger picture in favour of acting all righteous and outraged.
-I was far more interested in Astra/the Deceiver's past relationship than Mary/Michael's. Mary and Michael were sweet together and I was happy they got their HEA. But they weren't as intriguing as Astra and the Deceiver, who seemed to have more angst, mystery, and history. I would have loved to read about them, I wanted to know if they ever got along with each other, if they were ever romantic, if they once had feelings for each other, when and why their relationship was destroyed, and if they still loved each other in some sort of twisted way. Their relationship was so much more enthralling.
-Why was the Deceiver evul? He was greedy, shallow, and power crazy, and didn't care at all about destroying other people. Why was he like that? Why did he hate Astra when they were soulmates? How could Astra and the Deceiver be soulmates when they had such differing attitudes, ethics and morals?
All in all, a decent end to the duology. Mary and Michael got a lovely HEA by getting the boring, uneventful life they'd always wanted. The only thing was truly disappointing was not getting more of Astra/the Deceiver's story and history.