During the whole book one of the main figures, Sydney, thinks about killing other people. Of course, he's a writer he has to imagine such things, other people in the story say. Nearly in every detail he imagines how he would kill for example his wife. And when she leaves him he plays as if she was really dead and it seems as if she was on the way to play this game with him. But his wife isn't dead. She's still alive but she doesn't want to see Sydney again and she doesn't want to come back to her parents because she's ashamed because she has been away for such a long time.
But didn't I buy a mystery story the reader asks himself. He can see that there's a lot of talking about murder but no-one gets killed by an other. Still the book takes an ending in a very special way, in a way no-one would expect it to happen.
So we may say that Patricia Highsmith keeps us on tenterhooks nearly until the end of the book - because we are all waiting for a murder and really don't know if it will happen. And we can also never be sure, that the murder (if it is going to happen) will happen in the way we could imagine it. We are always uncertain about the next thing that will happen. But exactly this is how Patricia Highsmith holds the tension inside of us high, very high.
I really enjoyed this book because it's full of tension from the first until the last page and you as the reader may never know what will happen next. The book is also full of special personalities who are worth to be known by us. The figures have thoughts which I can't imagine that they will cross my mind once but it's very interesting to see how other people may think or react if the situation becomes real or seems to become real.
The book really takes us in another world, a world full of incertitudes although the reader does always know what Sydney thinks. But there are all the other people who think differently about Sydney and this always produces a feeling of incertitude in us. The reader doesn't really know if he may trust Sydney or if Sydney will do a thing to change the image we have of him. This also holds the tension on a very high level. Your feelings will change through the lecture at the end of the book you will think differently about nearly everyone in the book than you did in the beginning! So, just read it and let you be taken through this change of feelings!