I like the mystery, but absolutely love the interactions between Roan and Paris. Sometimes the story spends too much time in the details, which sadly slows down the plot. There is a major spoiler in the next part of my review, so beware.
I was not expecting so much heartbreak when I started this series! You knew Paris would die during the entire book and sadly there was no miracle that saved him. I definitely respect the author for this though, only it breaks my heart. I absolutely love Roan and Paris together and how they interacted, so I'm not sure how the next couple of books will play out without Paris. I'm already feeling resentful towards Roan's next love interest (hopefully that won't happen for a long long time), which of course isn't very fair of me.
The book has a great balance between mystery and romance. And going into this series I wasn't expecting the strong point to be the romance aspect of the story, but more the mysteries. Though after reading Infected #1 & 2 I find myself loving this part of the story first and foremost. So I was a bit disappointed to miss out on most of the trip to Vancouver (wedding/family), which would more likely be included in a romance book. Since the romance part will probably be lacking in the next book, I'm wondering if I would like it as much as the previous 2 books. I also like Roan's (new) lion/virus child abilities a lot, so I hope that will be further developed during the series.