Well researched history of John Dodd and his tea business in Taiwan, and the history of oolong tea.
Which is interesting, oolong is almost the default tea option in Taiwan these days, and one of the most popular gift options (Oriental Beauty Oolong) that we gift when travelling overseas.
Turns out it started as a tea that no locals wanted to drink. Something no on believed in.
I also appreciated the little titbits of tea knowledge and tea history put in at the end of each book. I once did a translation for tea making and that was reading material for days, so having a pared down, easy to understand version was a treat.