For the first 40% or so, I was enraptured - the writing, atmosphere, and hints at magic and faeries felt like a fairytale. It was a little slow, though the plot picked up in the second half. But the lusty romance elements irritated me. Without checking, Upon a Starlit Tide felt distinctly YA to me, only because there was a big emphasis on romance and physical moments. But the themes and complex characters were certainly adult, so there was a lack of cohesiveness in intended audience. I found our main character Luce's pendulum attraction to both Morgen and Samuel annoying more than interesting. She had only just met Morgen, and he was being way too handsy right off the bat. It felt very YA "mysterious, dark stranger who makes me feel desire is who I want" of Luce. Besides this main issue, I enjoyed the mishmash of Cinderella and Little Mermaid elements. I did not find the mermaid plotline overdone or dull; I enjoyed the unique aspects of "sea-maids" and their powers in this book. The characters were certainly interesting. Luce has a tempestuous relationship with her sisters, where moods swing violently from caring to cruel, and favor is there one day and gone the next. In one paragraph, she is bullied, encouraged, and competed against by her sisters. Especially with how their interactions develop, you can tell that Luce feels familial love towards them but that the relationships are not the healthiest. Jean-Baptiste (Luce's father) was also infuriating and mysterious as a character, and I'm satisfied with how things ended up between him and Luce. I liked the fae element very much, as I love traditional fae folk in stories. I wish there would have been more involvement, but we did have a significant amount of time with one fae character in the later parts of the book, so I'll have to take what I can get. And anyway, the lack of fae interaction fits with the background crisis of the book, that the fae are leaving the human-occupied lands and are taking their magic with them. Finally, for plot specifics - the pacing in the second half ramped up to 2x speed. Everything was moving quickly, and I feel character development was sacrificed, especially between Luce and her sisters, and even between Luce and her love interest. I also did not really like how the last chapter ends (before the epilogue), but I do think it was fitting. So, I will not count it against the story. (The epilogue remedies this immensely, by the way.) Between the unnecessary romance drama, complex characters and relationships that were not examined enough, and varying pacing, Upon a Starlit Tidewas not a perfect book for me. BUT, it is now one of my favorite mermaid books as a result of the tone, atmospheric setting, lovely writing, and unique elements like the stormstone. Also - I saw someone else mention this, but the audiobook is amazing EXCEPT for the fact that Samuel's voice sounds like a grizzled 45 year old fisherman, not a 20ish young man. Keep that in mind. . . Thank you to Macmillan Audio for the gifted audiobook copy. All opinions and thoughts are fully and genuinely my own.