I like that there are effectively two mysteries going on and that one of them surrounds Mao. I'm not sure where it's going because it should (based on the acknowledgement) be a critique of Mao, but I'm still not sure in what way.

There's also the mystery of the fictional Jiao and Xie, though they seem to be taking second place to Mao (which also functions as a critique because the reason they're being investigated is because it is believed that they are blaspheming against Mao and selling information that could "hurt the Party image").