With Requiem for an Assassin, the latest in his series about half-Japanese, half-American assassin John Rain, Barry Eisler has produced one of those thrillers that is hard to put down even when you need to, say, go to work or sleep. This book served as my introduction to Eisler but I am definitely going to go back to read some of his earlier novels. The book is not flawless - Patrick Anderson in The Washington Post notes one plot hole - but it's definitely an exciting heart-pounding thriller in every sense of the word.

I had the pleasure of interviewing Mr. Eisler recently via email.

What did you set out to do with this book? Did you achieve that goal?

On the most obvious level, I set out write a thrilling story. Judging from most reviews and reader reactions, I've succeeded.

But the thrill is more the end... the means I wanted were a deeper exploration of some of John Rain's internal conflicts, a crisis produced by the desires of his heart and the imperatives of his nature. I think these means were successful, too, but leave it to readers to decide for themselves.

This book is part of a series, right? I must confess I have not read the others in this series. Would you summarize for me, and the readers of this interview, what has happened so far in this series and what this book is about?

Yes, Requiem is the sixth book in a thriller series about a half-Japanese, half-American assassin named John Rain, whose specialty is making the hit look like natural causes. In the first book, Rain Fall, Rain is living an isolated existence in Tokyo, aloof from the society around him. As the series progresses, he begins to form attachments — a friend and partner, former Marine sniper Dox; and a lover, Mossad agent Delilah. Those attachments create complications for him, and never more severely than in Requiem.

What kind of research did you do for this book? I am particularly curious about the topic of torture during war-time since that came, I think, after you left the CIA. Was that something you saw done or researched by interviewing others or what?

As always, I visit all the places I write about and describe things as I find them. I also talk to experts on a variety of topics, in this case, various forms of interrogation.