This is by the guy who wrote Shogun, which I loved, but about traders in China instead of a guy stuck in Japan. It started out slowly and very much as if I'd missed some previous book in the series, and I wasn't sure I liked it, but I sort of remembered feeling that way about Shogun in the beginning, so I stuck with it and loved it by the end. It's a long read, but a couple of days in a place without TV or internet, a couple of two hour plane rides and babysitting for a few hours after kids had gone to bed allowed me to finish it in record time.

Also it was great; you should read it.