Heroes of the Zeroes is Nick Rogers’ daily, alphabetical look back at the 365 best films of 2000 to 2009.

The still-unidentified Zodiac — a serial murderer who made Northern California his own private ant farm throughout 1968-69 — had but five confirmed kills.

But add as (mostly) living victims Robert Graysmith, Paul Avery and David Toschi — a code-breaking cartoonist, a crime reporter and a San Francisco police inspector, respectively.

All were brought to their knees giving futile chase to a manipulative, media-savvy madman with bizarre cryptograms as menacing as his homicides — during which he often offered illusive safety or made targets complicit in their demise.

David Fincher’s 2007 Zodiac drilled into dark pathologies of each man’s process — anxiety, compulsion, uncertainty, miscommunication, territorialism — and directed Jake Gyllenhaal (Graysmith), Robert Downey Jr. (Avery) and Mark Ruffalo (Toschi) to stupendous specificities.

It also tracked how, with homicidal tendencies in hibernation, the Zodiac’s rampage was easily compartmentalized into crowd-pleasing pop culture via Dirty Harry.

Zodiac is not without wry humor or unexpected character details (the Zodiac’s targeted couples display power dynamics before they’re stolen). But the onus of obsession is Fincher’s foremost goal — desperation for definitive answers that obscures danger.

Zodiac rides in a paranoia rumbleseat all along, but floors it over potholes during a spine-tingling climactic basement scene — evocative of how discovery and understanding come to supersede sanity, safety, justice or reason.

So insistent, and successful, is Fincher at duplicating that hypervigilance that, by film’s end, you may try writing a “k” in two, not three, strokes to see the difference — damning and admiring how Fincher’s indisputable masterpiece has dragged you down that rabbit hole.