I just finished the 47 Samauri.

Not a bad book but of course it requires you to suspend disblief to make it work. Instead of buying the hardback in a years it will be a paperback at 1/3rd the price.

As for a good movie script, perhaps, but I think it's already been done by Sidney Pollack.

Find the 1974 "The Yakuza" and see how great it is, staring Robert Mitchum and Ken Takakura.
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