Book Review: I See You by Claire Mackintosh

I had seen a couple of positive reviews on my social media for I See You by Claire Mackintosh so I borrowed it from my local library, and here's what I though of it..

Zoe Walker is a 40-year-old woman who travels on the London Underground on a regular basis for her commute to and from work. 
One day, she comes across an advertisement in the classifieds section of a newspaper, which shows a photo of a woman who looks eerily similar to Zoe. 
When she shows the advertisement to her family (partner Simon, and grown children, Justin and Katie), they try to reassure her that the lady in the photo is not Zoe, but in fact just someone who has a strong resemblance to her. 
Even her neighbour and long-time friend, Melissa, thinks she is overreacting.  
But the following day, she notices another advertisement, this time with another woman's image. The ads feature nothing else except for a website address and a phone number.
More of these bizarre advertisements follow, until Zoe realises that there is a pattern forming, and decides to try and uncover the truth as to why this is happening. 
She contacts the police, but she isn't taken seriously at first. 
It isn't until the women in the advertisements become victims in a spate of crimes that the Murder Investigation Team realise they need to take action before something sinister happens to Zoe...
PC Kelly Swift assists with the investigation, and I enjoyed her character.  I found that she added an extra dimension to the story, and I liked reading about Swift's background as it was uncovered. 

There are a few moments of excitement throughout this psychological thriller, but nowhere near as much as I was hoping for.
The ending was quite good, and somewhat alarming, but I couldn't help but feeling that I wanted more from this book. It was a little predictable and far-fetched for me to fully appreciate it. 
It's a shame that it didn't quite deliver for me, but I'd love to hear your thoughts if you've read it, or plan to, as it has been getting some rave reviews.