REQUIEM FOR AN ASSASSIN by Barry Eisler. New York: G.P. Putnam's Sons, 2007, 356 pp., $24.95 (cloth)

Freelance assassin John Rain, featured in five previous works by Barry Eisler, is running out of enemies in Japan. And friends as well. Several books back, his computer geek buddy Harry was set up by a lovely seductress. Then Tatsu, Rain's mentor at National Police Agency, died of cancer, leaving the biracial, multilingual, high-tech hit man for hire increasingly detached from Japan.

The yakuza hoods and corrupt bureaucrats with whom Rain previously contended have departed the scene — usually horizontally and feet first — leaving Rain's tasks in Japan pretty much completed.

Likewise, Rain has also abandoned the notion of getting back together with his old flame Midori. He is now engaged in a torrid romance with Delilah, a beautiful and deadly Mossad operative whom Rain first encountered, and nearly killed, in Macau.