The film is made, finished, a story you've spent years pursuing. Questionable cops, angry convicts, victims, perpetrators, passersby - you've lent them all your ear, given them a national audience and equal time.
Sure, you're a storyteller looking for a good yarn, but your world isn't some kind of relativist nightmare. You believe there is truth out there, and you make this film to go after it.
But what do you do when you feel you've found it?
"Me, it was my job. I knew Randall Adams was innocent, and it was my job to prove it," says documentarian Errol Morris, who examined the murder of a Texas police officer in his 1988 film "The Thin Blue Line." On the basis of Mr. Morris's investigation and legal intervention, Mr. Adams walked free from death row. No film before or since has inspired such a reversal.
Now, as Oscar night draws near, "Capturing the Friedmans," a nominee easily as controversial as Morris's film, may be staking out similar territory.
The documentary examines the case of a father and son accused of molesting computer students in their Long Island home in the 1980s. On the basis of interviews by director Andrew Jarecki that reveal new information about the case, son Jesse Friedman - paroled after 13 years in prison - is seeking to have his guilty plea on 245 charges of sexual abuse vacated by the court that sentenced him when he was 19.
"Yes, my father admitted that he was a pedophile, [but] I am not a child molester, and I don't think it's appropriate for me to have to answer for the sins of my father," he says on camera.
That puts Mr. Jarecki in a tough position. Critics overwhelmingly praised his film, released last summer, as evenhanded and provocative. Though it does imply an injustice has been done - that father Arnold Friedman, who died in prison in 1995, had previous sexual contact with minors but not his students, and that Jesse was probably innocent - it carefully balances opposing views.
Several hours of supplemental footage on a DVD version released in January, though, paint a more damning picture of the investigation. An interview with an alleged victim casts his testimony into strong doubt, and interviews with detectives underscore the extent to which they coaxed and bullied testimony from Friedman's 8- to 11-year-old students.
Last week, two of these former students, now in their 20s, wrote an anonymous letter to Academy Awards voters urging them not to reward the film for making Jesse Friedman a celebrity. "We did not lie. We did not exaggerate. We were never hypnotized to tell our stories," they wrote.
Jarecki insists that, with or without the extra footage, his film is no apology for Friedman. He has, however, submitted an affidavit on Jesse's behalf to the Nassau County Court and is allowing Jesse to present interview footage to a judge in the hopes of reopening his case.
"This kind of film isn't really the format for [advocacy]," Jarecki says, "but the information in the film is what it is, and if Jesse wants to use it in his motion, that's his right."
Once you've released a documentary on such a controversial subject, says Jarecki, its resonance and repercussions are out of your hands. "Now the issue is transitioning to a new setting," he says, "and it's not a setting in which I have much relevance because the stakes are not mine."
But here's the problem, filmmakers say: Telling a story, any story, demands a dizzying number of difficult, subjective editorial choices. First, you choose your interviewees - and though you try to be fair, you can't talk to everybody. Some days you just make your best guess.
Then, in the editing, 90 percent of what you've learned falls to the cutting-room floor. Worthless stuff? Crucial details? How will your audience ever know?
"There's so much power in editing," says documentary filmmaker Charlie Thompson of Duke University's Center for Documentary Studies. "About all we can hope for is to be aware of the editorial pitfalls along the way. That's what I always keep in my front pocket - the remembrance that we are staying true to everyone who grants us an interview."
Marco Williams, a documentarian and film professor at New York University's Tisch School of the Arts, agrees. The best any of us can do, he says, is to "stand in the place where your personal convictions are, acknowledge that place, and try to give a truthful interpretation of the reality you see from there."
The style of documentary this implies - one that takes as a subject its director's own biases - is very much in vogue, and has proved wildly successful in films like Michael Moore's "Bowling for Columbine."
But the idea makes Morris uncomfortable.
In "The Thin Blue Line," he says, "you never see my investigation. You see the results of it, yes, but you don't see me following David Harris [who at the film's end obliquely confesses to murder] around for five months afraid for my own life."
That kind of exposure would have been gratuitous, Morris says, because everything about the film speaks to his own preoccupations and artistic vision.
Sometimes to a fault. Morris admits he walked a fine ethical line in researching the story. Trained as a private investigator, he used access to interviewees and records granted him as a filmmaker to conduct his own investigation of the case. In the end, he says, it was that meticulously gathered evidence, not the film, that got Adams's conviction overturned.
Though Morris did have qualms about his dual role, he says his certainty that Texas was preparing to execute an innocent man trumped those concerns.
"I'm not saying there's no such thing as a general ambiguity in the world, but I think there are some questions that have answers, and those answers have to be pursued," he says. "Thinking doesn't make it so. There is a real world out there, and I think it is our job to try to understand it."
Jarecki says as far as the Friedmans' story goes, though, his job has come to an end.
"The Friedmans are a complex group, and not much more fun to work with than they appear in the film," he says. "Still, they are entitled to the freedoms they have under the law."