The first of these was I Let You Go by Clare Mackintosh, a former police officer turned bestselling author, who gave a very good talk about her transition to being a writer, and how her previous career informs her writing. The book sounded interesting, not least because of "The Thing" that apparently happened partway through and blew everyone's mind... So, I picked up a copy and read it last week, while away at a writing retreat.
The book is about a hit-and-run accident, following the police investigation, and also the stories of other people involved in the case. Now, having read the book, I'm not exactly sure what "The Thing" actually is. There are three big reveals in the book, and I think "The Thing" is probably the first one. However, I figured out the first two on page 11, and it would have been impossible to guess the third one as there was no build-up to it at all, which made it rather more of a "huh" moment than an "OMG". I don't know if the clues on pg 11 would have been so obvious if I hadn't been primed to look for "The Thing", but there are multiple references on the cover of the book to an "amazing twist", so it's clear the reader is supposed to go into it expecting big surprises.
I didn't really connect to any of the characters - I lost sympathy with the two police detectives quite early for various reasons, and neither of them stood out particularly strongly anyway. Plus, "The Thing" made it difficult to get a handle on the other main character in some ways. Then, in the second half, a new narrative thread was introduced that was really unsettling and very creepy - incredibly effectively written, but not a pleasant experience to read at all.
So, throughout the book, I was only really reading it to find out what happened in the end - which I suppose still got me to buy and read the book all the way through, so is perhaps a valid marketing technique. It was well written, and presented a particular type of relationship and mindset very credibly, but it wasn't really my kind of thing, and I didn't find the conclusion all that satisfying.