This one is one of them that I don't remember all that well. You'd think I'd remember this one better then the first few in the series, but it seems to be the other way around. It's been a while since I've read a book for my In Death re-read, but I never seem to have a problem getting back into the series. Part of that is likely because I've already read them.
Eve focuses very quickly on a suspect and never changes her idea. I found that a little strange, but I'm not surprised that Eve was right. She does sometimes focus on the wrong person. Eve saw something in the suspect that we, the readers, don't see. Some of it is, I think, basic dislike from the start.
In the end, the name of this book is a big hint as to how this murder was set up. Strangers on a Train. There is not train, but the idea is the same. I only caught that after I finished the book and started sorting out all my reading sites.
Since Eve has a suspect so soon in this one, it's less of a murder mystery and more a motive and opportunity one. The suspect has an alibi for the time of death, and it seems like everyone else does until Eve has one of those sudden understanding things I hate (it's even worse in TV shows, since we don't get the person's thoughts).