This is the second entry in Don Winslow's Neal Carey series, from back in 1992. According to Amazon (as I type), a used paperback copy will set you back $19.99, a new hardover goes for $300. But the Kindle version is $9.99, and it's worth it.
As the book opens, our hero Neal is recuperating from the events set forth in the first book, reading his beloved Tobias Smollett in a primitive house on some isolated Yorkshire moor. But his "Dad", Joe Graham, pulls him back to America for another unlikely assignment: an agricultural scientist has gone missing in the San Francisco area. His agribusiness company asks for help as one of the "Friends of the Family", the quiet Rhode Island bank accustomed to doing extraordinary favors for its clients.
So Neal heads off to Frisco, where he's just a step behind the scientist and a lovely, mysterious Chinese woman who's made his acquaintance. Neal eventually catches up with them in a sleepy Marin community full of artists and burned-out hippies. And manages to lose them again, while getting shot at for his troubles. Eventually, the trail will lead him to Hong Kong and China, and all sorts of hellish peril. As it turns out, Neal has been kept in the dark about what's really going on.
The plot is complicated, full of double-crosses, twists, dishonesty and betrayal. The narrative bogs down at points. The book is twenty years old, so some of its observations about China and Hong Kong are dated, and the prime motivator of the plot, once it's revealed, is ludicrous. Nevertheless, I had a good time.