There are several reasons why Zodiac should have been a disappointment. It a mystery story about a case which is still officially unsolved, meaning there's not going to be much closure by the time the credits roll. It's a David Fincher movie that is more low-key than his magnum opus Fight Club (or even his comparatively smaller follow-up, Panic Room). It's a true-crime period piece, which is typically a license for screenwriters to take a real-life story, infuse it with cliches, and then pass it to a director to add some obvious period details and lame music cues.
Zodiac, however, is far from a disappointment. This retelling of the Zodiac serial murders that struck the San Francisco area in the late 1960s owes a lot to its excellent cast. Robert Downey Jr. is, as usual, a joy to watch, stealing almost every scene as gonzo, alcoholic crime reporter Paul Avery. Mark Ruffalo takes this opposite tack for his character, Dave Toschi, a soft-spoken detective with a Columbo raincoat and a taste for animal crackers (Ruffalo has more scenes eating than almost any actor since Brad Pitt in Ocean's 11). Jake Gyllenhall has the central role, though, as Robert Graysmith, the cartoonist turned amateur investigator. Gyllenhall's perpetual youthfulness works for him here, as it underscores his character's inexperience compared to his colleagues in the newsroom and the police he turns to for assistance. Rounding out the cast are the ever-reliable character actors Brian Cox and Philip Baker Hall, as well as Anthony Edwards and Chloe Sevigny.
The movie, shot on high-definition video instead of film, looks phenomenal. Fincher has (save for one montage) toned down the stylistic tricks of his previous work, but this is probably a good thing: his trademark shots of a virtual camera zooming through buildings and objects has become so co-opted by CSI and its clones that he's better off letting it go. The visual effects are still there, though; they just don't call attention to themselves. An overhead shot of a cab driving through the city, a breathtaking shot from the top of the Golden Gate Bridge, and a great time-lapse shot of the Transamerica tower being built are just a few of the special-effects shots that most people won't even notice. (Check out this site for some more information on the subtle use of visual effects in the film.)
I was also impressed by the way that Zodiac avoided the cliches of the serial killer genre. This isn't the typical "we have to stop the killer before he strikes again" movie. In fact, by the time Graysmith gets seriously involved in the case, the killings seem to have stopped, and the few people still investigating the case are doing so simply out of a need to find the answer. Throughout the film, captions supply the time and place of the action. The glut of captions in the first half-hour or so of the movie made it feel like an episode of Law & Order with ADD, but as the plot moves forward and the gaps between scenes stretch to months and years, it gives a palpable sense of the trail going cold.
For a serial killer movie, there is surprisingly little violence. The killings themselves are disturbing to watch, but they are of a completely different tone from the rest of the movie, which is frequently humorous (in earlier scenes, at least). There is one scene that juxtaposes the moods, as a young couple confronted with the Zodiac tries to talk their way out of the situation. I was laughing at it until the violence suddenly broke the mood. In addition, most of the violence is confined to the earlier section of the movie. There's not a car chase or shootout to be found here, although there are plenty of scenes of cops in several counties arguing over jurisdiction and trying their best to share information. At one point, Toschi walks out on a screening of Dirty Harry (a film loosely based on the Zodiac) and complains about the unrealistic vigilante cop. I guess this is the sort of movie to which he'd give his approval.
The film isn't perfect. Although the ambiguous ending is true-to-life, it's still unsatisfying (although that's probably the point). In the category of "Jake Gyllenhall movies where he ages 20 years over the course of the film, this one is disappointing compared to Brokeback Mountain (as far as I can tell, all he did was grow a couple of days of stubble). And has there ever been a film in which a man becomes obsessed with finding the truth and/or catching a criminal and it doesn't end up destroying his marriage? They could have included a scene where Graysmith carves a bust of the Zodiac out of his mashed potatoes and it would have gotten the point across just as well.
Despite those few flaws I was able to find, Zodiac passes the core test of worth-seeingness, namely that I was unable to tear myself away once I started watching it. Time will tell if it will stand up to repeated viewings (I plan to check it out at least once more, perhaps next year when the director's cut DVD drops), or if the Academy Awards are aware of its existence in a few months (may I suggest Mr. Downey and Harris Savides for the cinematography?). The fact that I've now written an epic blog post based on the film, though, strongly suggests that this will be something I keep coming back to.