Zodiac is a fine movie, but a colossal disappointment. Clocking in at two hours and thirty-eight minutes, it is too bloated for a tale of murder and obsession and too short to reconcile all the facts in the bizarre and horrific true case of the Zodiac killer. Not until late in the movie does the real story kick in, which is Robert Graysmith’s (Jake Gyllenhall) strange obsession with the killer and the way his own private investigation begins to take over his life. Fincher and his editor, Angus Wall, should’ve made some hard decisions in the editing room and confined it to this story.

Instead, Robert Downey Jr. and Mark Ruffalo’s characters get lots of screentime that amounts to very little. The movie, in which every scene seems to start with a subtitle saying ‘four months later’ or ‘two and a half weeks later’ or ‘three years later’ becomes a monotonous recitation of dates and facts. More visual transitions, like the beautiful shot where the Transamerica building is constructed in time-lapse, would’ve been appreciated.

You do have hand it to Fincher on one account: he has likely been offered every sick serial killer movie in Hollywood since making Se7en and has turned them down. Now that he has made this true-life epic, maybe people will leave him alone. Aside from the murder scenes, which are horrific but accurate, Zodiac eschews sensationalism and rudders steady through procedural waters. Even if it doesn’t debate the interesting issues surrounding the case, at least the movie raises questions about the responsibilities of journalists, government officials and parents when a fame-seeking killer, for example, threatens to kill school children on a school bus.

There are some great nail-biting moments. Graysmith’s visit to a creepy movie buff is the best of them, although it ends up making little difference in the total plot. In the end, there are too many scenes that, like false leads, go nowhere. What of Ione Skye’s lucky victim character or the Zodiac’s strange interest in Marvin Belli (Brian Cox)? What about the extra letters at the end of the Zodiac’s cryptogram? Sticking to the facts is one thing, but one can at least afford to be selective.

The Zodiac killer’s identity is not this movie’s only mystery.

Why does Robert Graysmith, for example, not immediately take his wife and children far far away after he gets a call from Zodiac? Why does Paul Avery (Downey Jr.) descend into booze and drugs and not Inspector Toschi (Ruffalo)? As an examination of the darkness of the human soul or the nature of obsession, Zodiac is missing part of the evidence. As a recreation of the facts of a true crime story, Zodiac is little superior to an A&E documentary and positively inferior to HBO’s The Wire.

As for the film’s technical achievements, they are unimpeachable. I’ve already blogged about the revolutionary digital workflow. I saw the movie digitally projected and it looked great. The sound design is intense; I will never again hear Donovan’s “Hurdy Gurdy Man” without getting chills. The art direction, costume design and cinematographical color scheme heighten the period effects without going overboard. Many images are haunting: cars crossing the a fog-shrouded Golden Gate Bridge as if driving through the sky, the masked Zodiac killer cresting a hill or lumbering away in the night.

One can’t help comparing Zodiac to the far-superior JFK which also had historical re-enactments in the context of an obsessive investigation. JFK managed to balance DA Jim Garrison’s story with a massive amount of investigative exposition and still remain dramatic and coherent. Zodiac could easily be re-cut to find such a balance. And that, not the unsolved murders, is what makes Zodiac a tragedy.