As with Kobek's series as a whole (the first of the duology, MOTOR SPIRIT, is quite excellent – and I do recognize that I might have done a disservice by reading them so far apart from one another), there are two books in HOW TO FIND ZODIAC: one, an utterly compelling examination and portrait of not only the pre-internet internet of fandoms and fanzine culture but of the collision of that culture with right-wing, anti-government ideology and Cold War paranoia; the other, half a portrait of a deeply disturbed man, Doerr, one whom I could readily believe would commit a reign of terror to prove his own unappreciated genius to the world – I do agree, wholeheartedly, with Kobek's portrayal of the killings as the late 60s, pre-internet equivalent of today's mass shootings (if Zodiac were active now, he'd be livestreaming) – but still only half a portrait: I wanted to know more about Doerr, beyond the screeds and personal ads, the married father with a secret double (or, perhaps, triple) life. Maybe that was intentional, maybe not, but I was, nonetheless left wanting more, hoping that, eventually, we'd get to it. We didn't: the final page left me with the impression that I had read half of a book, a deeply-drawn and exceedingly well-researched portrait of half of a person - but then again, maybe I didn’t take the title of the book literally enough.

That being said, while Kobek's theory is, by far, the most compelling one put forth, I never had that oh shit / eureka / evidentiary moment that fully convinced me that Doerr was Zodiac (though the sketch, devoid of glasses with added mustache, came pretty damn close). Perhaps I missed something – or perhaps the other half of the book, the missing half, would finish the job?