This one didn't quite do it for me unfortunately. Personally, I love an unreliable narrator - I love a story when you can't quite trust what anyone is saying or doing. However, by the time the twist came around I felt like I had been waiting an age for the story to pick up the pace and was becoming disinterested with the convoluted plot.
Michaelides introduced a whole range of shifty, unlikeable characters, and then proceeded to end the story, but I felt my opinions on them hadn't been changed and I was unsure on their relevance to the plot other than to flesh out a mystery plotline.
I also spent some time considering whether I was less invested in this book because it was written by a man - I found our male protagonist unsavoury from the first few pages and this continued through the novel. However, it's possible that this was an intentional stylistic choice that I'm remarking on and in which case, the author was successful in manipulating my feelings right from the beginning - take my negative-ish review with a pinch of salt perhaps!
As a quick holiday read, it was interesting enough and I can see why it was so popular recently!