I'm going to cut to the chase. This book was alright, though on the lower end of that spectrum. The plot was fine, if not a little rushed at the end. But then again, this was the author's debutant novel, published on the first draft.
You know that one teacher in that class who assigns a 2,000 word essay and you can wrap up the topic in 500? It's almost as if AJ Finn's publisher demanded 100,000 words and he himself could only muster 40,000.
While I did enjoy the read toward the end, as others have said, the book starts super-duper slow. 200, may even 300 pages of absolute waffle with enough syrup to satisfy the whole of Quebec!
You could read chapters 1 - 10, 80 - 85, and 95 - 100, and have completed the book's entire plot, including the two primary 'twists'. And you wouldn't miss much, really, not even the effect of the second twist, because the secondary character's interactions with the protagonist, Anna, were typically very scarce, spread-out, and not well-invested (especially emotionally).
Hence, the twist wasn't much of a shock, or much of a great one albeit concealed decently (for someone who hasn't read much YA thriller/mystery). Without spoiling it, the emotional facet of Ethan and Anna's relationship could have been developed for the twist to hit harder toward the end of the book, especially as it felt rushed and abrupt.
That said, Finn seemed too fixated on presenting Anna's flawed narration within the book to accompany the plot, that, red-herrings and other flawed characters otherwise were not characteristically developed well-enough for me to care of their role in terms of Anna's internal psychological thrill.
Perhaps that wasn't the intention of the author, but he certainly could have made better use of the first 200, maybe 250 pages. There's only so many times you can write short sentences with fancy adjectives and verbs on wine, film noir, and Merlot.
I'm focusing on the negatives here, mainly, but hey, it is what it is. I liked the idea, writing style was alright, and plot was decent although could have been shortened and better executed.
3/5 stars from me.
Edit: Thought about this book randomly, whilst brushing my teeth. Soooo, I'm coming back to this after a year, almost. When I wrote this, I was under the euphoria of reading for the first time in years: hence, my perspective was skewed.
I revoke my 3/5 stars and give it a 2/5. Save your money - rent it from a local library at best. Your mileage may vary.