I read this after the excellent "devotion of suspect X" by the same author. "Salvation" is not as good. Maybe because, to me anyway, the suspect and victim were initially hard to like, and mostly remained so, so it was hard to care whether the detectives catch the killer or not. The book revolves around finding how someone introduced poison into a cup of coffee. Each new theory or piece of information is discussed at length by the detectives and their pet scientist, galileo. The slightly larger cast of detectives - K now has two underlings, K2 and Y, as well as a boss M who is more involved -probably makes the Japanese tv series based on these books more sparky, as there are plenty of contrasting characters among the police to rub up against each other. However, in this book it just increases the number of permutations of two detectives having a very similar conversation about poison and coffee. After each conversation, in a total disregard for police procedure, a detective will leak any new info to one of the people under investigation. Their reaction to the piece of information will then be the subject of discussion between galileo-and-K, K-and-K2, Y-and-galileo, etc etc for another 20 pages. All the while, everyone drinks coffee. Or sometimes tea. Or sometimes instant coffee from a dirty cup. Noone develops a rational or irrational fear of coffee, except me.
After a dull middle of the book, there are some quickfire twists and reveals at the end, which do tie things together.
I loved "X" and may persevere and try another by this author.