Jake Gyllenhaal, investigator
David Fincher's film, Zodiac, definitely explores such ideas. Zodiac concerns an investigation into the identity of the notorious serial killer who terrorised southern California in the late 1960s and early 1970s. In real life the killer was never caught and there remain several plausible theories as to who it might have been. But Fincher's film isn't really so concerned with the Zodiac himself or why he committed these murders- he can't be, we just don't know, as with the effects that those murders had on those investigating them. The film is about the investigators- both a pair of journalists and a pair of police officers- who for a variety of reasons become deeply involved within the case.
Three of these characters become deeply involved because of their roles, as the officers assigned to the case and the San Francisco Chronicle's crime reporter, but one of them doesn't have any such direct connection. For him and increasingly for the other three the Zodiac is an intellectual phenomenon. He tells his wife at one point in the film that all he wants is to be able to see the Zodiac and know that that is the man who terrified all those people for so long. There is no sense of justice in this. Afterall the Zodiac committed according to the police officer at one point, only 5 murders, whereas there are hundreds of murders in California during the time he was active and almost certainly unsolved murders as well by the legion. But this man presented a conumdrum, he sent codes in ciphers which still defy the US police, he left very few clues and those that he did leave were contradictory. In addition, as he became more famous the chances of fake letters and phone calls rose, so there was also the question of which calls and letters to decipher.
One is tempted to say but this is the generation of Vietnam and Chile and countless other disasters. All the minds involved in searching for the Zodiac were tempted by the intellectual complexity but also by the simplicity. For taking on the question of Vietnam exposes one to all sorts of moral dilemmas- there are difficult choices to make every time you put down a foot. The Zodiac case though was complicated but also simple. Simple for it was clear- there was a murderer, there were victims, there was a problem. In so many intellectual problems there isn't such an easily graspable issue- the deaths of American soldiers have to be weighed against the deaths of Iraqi civilians for example.
Fincher shows us how these intelligent men became dominated by the cause. Behaving at times like a madman, the cartoonist Robert Graysmith loses his marriage, almost loses his children. The Crime Correspondent loses his job and perhaps his mind. The Policemen both end up transferring out of the department, one with issues hanging over him. All of them are upset by the clue that fails to yield. Graysmith in particular is shown as living in a twilight world, where every stranger could be the Zodiac, where every basement could be used to store murdered bodies, where suspision hangs over everyone. The investigation becomes his life. He turns himself into the hunter, and thus becomes hunted by his imaginary Zodiac in every window. The serial killer dominates his conscious life and he becomes taken over by that life- his escape at the end is through solving in his own mind the murder.
There is a sense in which intellectual pursuits can lead this way. In which seeing the world in a flower means that one's world becomes that flower. You can be taken over by seeing the essense of everything as part of a great pattern whose ultimate resolution is to be found in this particular instance. Films provoke this as well- they too are a pattern that we break down and solve and that as Zizek argues can become part of us, can dominate us. The Zodiac as a film suggests that there is peril as well as achievement in obsession. Fincher shows us what happens when a man or men in general are so dominated by one idea that their whole lives become dedicated to it. In a sense during an investigation, they become the investigator and that is all.
Definitely that is the place which Graysmith, superbly played by Jake Gyllenhaal ends up at. Indeed as he is the character whose inner life is really portrayed here, more than any other, it is within him that we can see this at its strongest. But other characters too end up as investigators rather than characters, they lose their humour, take to drink, lose their sense of self and hope for the future, all because of a killer, who has killed a fraction of those killed in the city over the years that he functioned in. They don't learn from this instance but the patterns they derive are false.
Fincher's film calls into question the nature of intellectual obsession, what if your obsession drives you into dark corners and believing that the nature of the world is darkness, you recede ever further into the black whole of a disturbed and suspicious mind. In this film it is neither the Zodiac nor his victims who are the focus, its the slowly disintegrating investigators, who swirl around the murderer, pulled in by the gravitational fascination that they feel to him, to seek light in the heart of darkness.