Ben Monroe is a social psychologist who spent time in Japan investigating a strange cult, falling for a beautiful Japanese woman,Kozue while he was there.
Years later,with a failed marriage behind him,Monroe returns to Japan trying to track down his former lover. His estranged daughter Mazzy reluctantly follows but is entranced by a Japanese folk tale told to her by the man in the seat next to her. The man,Kori, steals a tag from Mazzy's luggage and begins to track her. With Ben's search taking him deep into the shadowy underworld of hostess clubs and red light areas he doesn't realise that a curious Maddy is following him,and she doesn't realsie that Kori,who recognises Ben from being in the cult he was investigating,is following her.

This is an involving story but definitely a slow burner and I'm not sure it merits the "thriller" label given by the publisher,not least as a major part of the tale is told after the event after quite a gripping build up.
If that sounds as if it's a damp squib,it's not as it's very well written but it feels almost as if the handful of violent incidents in the story have almost been redacted and mentioned in passing rather than major parts of the story,which I found quite odd.

Enjoyable and well-written but flawed,or maybe I just didn't get it.

This is an interesting one to consider - A Sacrifice is a new book published 18 July 'now a major motion picture starring Eric Bana'. But it is also 'Tokyo' - named one of the "Best Novels of 2015" by The Observer. It's category description is Crime, Thriller, Mystery but at its essence and in its narrative it isn't really. The Bookseller describes it as having an 'engaging and pacy plot with entrancing writing in this expertly told dark fable of modern Japan'... but it's not really. Things might well get more confusing if you're a reader coming to this as a result of the movie, (Called A Sacrifice or Berlin Nobody depending on your country - but definitely NOT called Tokyo and not set in Japan.)
I mention the above in case anyone thinks this is a brand new book by the author.
So what of the book itself?
Ben Monroe is living in Tokyo - back years after his first travel to Japan and a failed marriage and semi-estranged daughter behind him.
When his daughter Mazzy comes (reluctantly) to stay with him, she does so as her father starts to search for a lost love he met in his twenties all those years ago. What neither he nor his daughter knows is she has attracted the attention of a cult survivor.
That short plot description actually makes the book sound more 'crime/ mystery/ thriller' than it actually is.
In reading it, it's actually a much more slow burn examination of being an ex-pat, family, relationships and history. The Japan Times praised the book, saying 'if only all ‘foreigner in Japan’ novels were this good’. I've read a lot of 'foreigner in Japan' stories and it does work in this way - this isn't a gaijin fully emersed in the society the way non fiction work like Tokyo Vice/ Noir show, so when the author gets some cultural descriptions 'wrong' or 'incomplete' I didn't see it as being incorrect facts more as a 'not fully accurate narrator'. In this respect the book worked well for me, and I enjoyed the writing.
I have no 'need' for a book to be crime/ mystery - but I do think some readers who are expecting a 'Taken' style thriller might be disappointed in this more measured/ slight narrative. Without plot spoilers, things do take a more dramatic turn in the last chapter or two, but even that is 'off screen' and are wrapped in a more dream like section which seemed designed and applied to defuse the very nature of thriller 'conventions'.
As cliched as it is to say '(location) was a character itself' it really is the case that Tokyo IS a key part of this book - the way it is and the way foreigners react to it. I enjoyed the book for this, but it does make me wonder if the movie adaptation of it is going to resemble the book in any meaningful way...