What intrigued me the most about Hourglass was the blending of paranormal and science fiction. Normally, I wouldn't put the two genres together, but I thought it worked well. 
 I really liked the time travel and schools for people with different abilities. There are rules to time travel and such- they aren't explained, which didn't irritate me like it normally would. I thought it worked, though, because most of the novel was laying the groundwork for the rest of the series. 
 The romance was okay, with the seemingly required love triangle. There is a definite (and immediate) connection between Michael and Emerson, which makes sense, given their abilities complement each other quite nicely. But there's also something between Kaleb and Emerson, but for now, I'm chalking it up to Kaleb being very empathetic. 
 There is something very epic about this book. I also liked that it was slightly unpredictable. And the setting? Tennessee was interesting, but not what I pictured. For some reason, I kept picturing Georgia or South Carolina. 
 I liked it enough to give it a 3 out of 5, but not enough to keep reading the rest of the series.