Let's get one thing perfectly clear. Zodiac is not Seven Part 2. This film does profile a serial killer and it was directed by the enormously gifted David Fincher, but it's an entirely different kind of movie. Instead of repeating himself, Fincher opts to go a completely different route, and the end result is Zodiac, a sprawling, ambitious expose on the famed Zodiac killer - a monster of a man who struck panic into the heart of a nation back in the late 60's and early 70's, by committing a random series of grisly murders.

For those who know the case, you're already well aware that it was never closed, because the Zodiac killer was never actually brought to justice. What Fincher does with this film, is give us an epic look into the lives of those the killer destroyed. Not only the numerous murder victims, but those who became immersed in the case. The law enforcement, the press, and average every day citizens who weren't only terrified by the random killing spree, but, in some cases, obsessed with discovering the Zoidac killer's identity.

Zodiac is multi layered in it's exploration of this subject. It's as if the entire case has been painstakingly transferred to the big screen. At it's heart, the film is a complex and in depth procedural drama, but it's also a movie about obsession, particularly when the story focuses on cartoonist turned novelist Robert Graysmith (he would go on to write the book on which this movie is based). As a slightly withdrawn boy scout of a man, Graysmith (played by Jake Gyllenhaal) would merely start out an amateur sleuth intrigued by the Zodiac killer. By the end of his journey, however, he would be completely consumed by this exhausting case. So much so, that it would ultimately put a strain on his relationship with his wife and kids, and finally, his own well being.

The bulk of the film focuses on law enforcement's frustrated but determined efforts to bring an end to the horrific killing spree. Inspector Toschi (Mark Ruffalo) and his partner William Armstrong (Anthony Edwards) would stop at nothing to solve the case, but in the end, the killer would elude them, even though they had a pretty clear indication of who the guilty party might be.

Zodiac is methodical in it's pacing (and runs at a long but never dull two hours and forty minutes), and this will, no doubt, bother some viewers. This film doesn't move like a bullet train, and it isn't one of those mystery thrillers working towards some big reveal or payoff. The pacing serves a distinct purpose. As for the final moments? Again, the case was never officially closed, but Fincher and crew don't end the film on an ambiguous note as I suspected they might. Instead, Zodiac points a finger but I wouldn't call this a reckless leap of faith. Exhaustive and extensive research have lead not only the film makers, but those who were close to the case, to come up with a conclusion. In this respect, Zodiac the film has a certain Oliver Stone aura to it. You could draw comparisons to JFK, granted, this picture keeps things a little more low key.

Zodiac is shocking in it's realism, particularly in the first act when we are witness to a few of the killer's murderous rampages. In one bit of nausea inducing brutality, the Zodiac killer ties a couple up lake side, and proceeds to stab them repeatedly. Shockingly, one of the victims survives the horrific ordeal.

David Fincher has displayed time and time again his gift for establishing tone. There are several moments of undeniable dread in this picture. Be it an ominous sequence in which Graysmith is lead to a dark basement by a potential suspect, to a creepy scene in which officer Toschi and his partner interview a prime suspect, to a gut wrenching moment in which the Zodiac killer abducts a mother and her infant child. There is certainly no shortage of scenes that will make your skin crawl. But Fincher also knows when to hold back showing a striking maturity as a film maker. Zodiac sort of plays as the polar opposite of Fincher's last film, the disappointing thriller-by-numbers Panic Room. That picture was a sheer case of style over substance whereas Zoidac is the flip side. Actually, that isn't entirely accurate. Zodiac has a distinct sense of style, but the entire film is understated. Fincher knows that the subject matter is compelling enough, and isn't about to taint the proceedings by over stylizing them. If anything, Fincher takes a classical approach in terms of the way he's shot the movie. He's meticulous with the tiniest of details. Zodiac feels like a film that might have been shot in the era it's depicting. Not only in terms of the film's overall look, but it's feel. There's an innocence on display that feels positively authentic.

Fincher also finds moments of humor in all this disturbing madness. Take for instance a scene in which Graysmith actually allows his children to assist him in his Zodiac research. It's a seemingly unorthodox conceit to be sure, but as played in the film, it's surprisingly light hearted.

Fincher has assembled a stellar cast. Mark Ruffalo gives one of his very best performances as Inspector Toschi. As a man who wants nothing more than to stop the Zodiac killer, Ruffalo is incredibly restrained and he's endlessly compelling without overplaying the role. There comes a moment when he must admit defeat, and he does so reluctantly. Once Gyllenhall's Graysmith enters his life, however, he's quick to unleash tiny details of information so that the case might be reopened. Gyllenhall seems slightly miscast at first, but he quickly finds his footing as Graysmith. As an everyman out to solve a case no one else has been able to put away, Gyllenhaal is terrific. As a man whose own obsession has overwhelmed him, he has some picture perfect moments here, none more so than his final one. After alienating his own wife and children, he gets to a point where he simply must know if his suspicion is the correct one. So, in a restrained final gesture, he sets out to find out. He gets his answer in the film's single most powerful moment.

Also turning in solid work are Anthony Edwards, Chloe Sevigny John Getz, Elias Koteas, Dermot Mulroney, Donal Logue, Brian Cox, Charles Fleischer, and a hilarious Robert Downey Jr. who livens the proceedings as a flamboyant reporter.

There are some things that don't quite work in the picture. For instance, the relationship between Chloe Sevigny and Jake Gyllenhaal is never truly explored, but that could be chalked up to the editing issue. Zodiac was reportedly over three and a half hours in it's earliest state, and it's too bad that the studio wouldn't stick by a longer cut. As it stands, Zodiac is mesmerizing from start to finish. It is, perhaps, Fincher's most accomplished work to date (this coming from a huge fan of Seven and Fight Club). The year is young, but Zodiac is, without question, the best film of 2007 thus far.