Another satisfying installment in the Jennifer L. Armentrout's Lux series. Opal picks right up where Onyx left off. Katy and Daemon's world has been shaken up in some very big ways, and they spend most of the book dealing with the fallout. Dawson is back and determined to save his girlfriend Beth, Dee blames Katy for her boyfriend Adam's death, and Daedalus is still enemy #1 and very much a threat to all their lives. And to make things even more complicated, douchecanoe Blake returns as well. Opal isn't a filler book, though. Far from it. Rather, it's a turning point in the series. Stakes are higher, emotions run hotter, and everyone is put to the test. With so much on their plates, Katy and Daemon's time together is constantly cut short or interrupted. Opportunities to bask in the glow of their newly-minted relationship are few and far between. It's frustrating, and yet it helps them too, bringing them closer together and infusing every private moment they steal with additional weight and meaning because those moments are so hard to come by. I've always enjoyed and rooted for Katy and Daemon's relationship, but this was the first time I really felt, in my bones, how right they are as a couple. The first time I got to see how well they truly work together. And yes, I was impressed. There's been a lot of talk about the cliffhanger ending. I won't lie, it's a doozy, but I can't say I was all that surprised by it either. It's almost....inevitable. But even knowing that, you'll still be gnashing your teeth because you have to wait MONTHS for the next book. That, my friends, is what we call torture!