So, the obvious first: no, John Rain doesn’t get killed in this book, but not for lack of opportunities. As the book opens, Rain’s in Manila to kill a bomb-maker at the behest of Israeli intelligence. With him is Dox, Rain’s new partner. The hit misfires when Rain makes a spur-of-the-moment decision not to kill the target after seeing him with his family– the target has a son about the same age that Rain was when his own father was killed. That brief moment of hesitation buys him a butt-load of trouble; while exfiltrating, Rain and Dox kill two people who are believed to be CIA agents. The Israelis are worried that Rain’s attempt will be tracked back to them, so they put the word out: John Rain must die.
Trust is one of the central themes of this book. Rain somewhat reluctantly comes to trust Dox after the shootout that ends Rain Storm— but as that trust blossoms, Rain comes to realize how much he’s missed being able to trust people. This is certainly a common problem among contract assassins, but us ordinary Joes can get the idea. As Rain attempts to figure out whether the two dead agents were really CIA or not, and thus dissuade the Mossad from killing him, he’s forced to make some hard decisions about who to trust, and how much.
Another key theme is redemption, for want of a better word. Rain begins to wonder if he’s done any good by his long string of killings, and if perhaps his energies might be redirected to killing evil people instead of whomever he’s paid to kill. Illustrating this, he considers the difference between the Japanese words roughly translating to “sword of justice” and “sword of oppression”. Some reviewers on Amazon have dismissed this introspection as sap or fluff, but I think it adds a great deal of depth to Eisler’s portrayal of Rain. Who among us has not looked back to consider whether his life has been well spent, and whether the remainder could be better spent?
As with preceding books, Eisler moves the action along at a racetrack pace. His descriptions of place are crisp and evocative (I particularly liked his description of Rain’s trips to the rural Philippines), and there is less emphasis on the minutae of Rain’s hand-to-hand fights with his opponents (more knife- and gunplay, though). Because I’m not a judoka, this made the book way more readable for me.
I can’t say much about the denouement of the book except that it sets out very clearly what’s going to happen in the next book, and that it contains a plot twist that I certainly didn’t anticipate that sets things up neatly. I’m eagerly looking forward to the next book, but I only have to say one thing until then: jazz goes with New Orleans. Highly recommended.
Update: I found this essay by Eisler that describes the backstory behind Killing Rain. It’s pretty darn interesting.

is this working?
i guess it is.
Hey Paul, really glad you enjoyed Rain’s latest adventure. I’m back from the 30-city promotion tour, catching my breath, and just about ready to dive into the next one. Hope you’ll enjoy it at least as much.
Cheers,
Barry