Did she or didn’t she? That is the question “Amanda Knox” explores with laser-like precision. Different viewers will come to different conclusions, but without doubt this strong documentary sheds a powerful light on this particular case while emphasizing the ultimate unknowability of absolute truth.

As directed by Rod Blackhurst and Brian McGinn, “Amanda Knox” does without a subtitle and frankly doesn’t need one. The case of the American college student twice convicted and twice acquitted of the murder of her roommate in Italy was such a tabloid and social-media sensation that a Google search reveals more than 7 million results.

That factoid comes from Knox herself, who is interviewed extensively here, as are her former boyfriend Raffaele Sollecito, the tenacious Italian prosecutor Giuliano Mignini who put them both behind bars, and the British tabloid journalist Nick Pisa, who reported extensively on the case.

One of the great virtues of “Amanda Knox” is that it allows all these key participants, and a handful of others, the chance to unburden themselves at length about their roles in a story, equal parts Alfred Hitchcock and Patricia Highsmith, that took eight years to play out.

Here, for instance, is Knox herself, articulate and self-possessed, thoughtfully summarizing her polarizing situation: “If I am guilty, I am the ultimate figure to fear. If I am innocent, it means everyone is vulnerable, and that’s everyone’s nightmare. Either I am a psychopath in sheep’s clothing or I am you.”

In addition to this wealth of interview material, directors Blackhurst and McGinn provide a large amount of court documents and archival footage, including a previously unseen video clip of the murder victim, 22-year-old Meredith Kercher, taken by Knox herself.

Just as disturbing is the visual evidence of the rabid way the case was covered by the media, with tabloid headlines screaming things like “Orgy of Death” and “Amanda the Man-Eater” on a daily basis.

TV newscasters were no better, with Diane Sawyer giving Knox an unapologetic hard time, and individuals such as CNN’s Chris Cuomo pounding her with questions like “Were you into deviant sex?”

Seen today, Knox, not surprisingly given what she has been through, is a serious and somber individual, living alone in Seattle and intending to work as an advocate for those wrongfully convicted.

In her pre-Italy years, however, video shows Knox to be much livelier, someone “quirky and ridiculous” who admired Xena the Warrior Princess. “I’m my own person,” is how she thought of herself, “but I’m going to find my place.”

A student at the University of Washington, Knox decided to become an exchange student in Perugia, Italy, to get out of her comfort zone and ended up rooming with young British student Kercher.

Just a week before the murder, Knox and young Italian student Sollecito meet and fall in love. Despite all that has happened to them since, both light up at the memory of how happy they were for that week, spending every free minute in each other’s company.

Then Kercher (inevitably something of a cipher here) is murdered, and two new people become key in everyone’s lives. These include journalist Pisa, someone who delights in the buzz of the scoop and is perfectly happy to spread the most salacious stories and theories, and prosecutor Mignini.

Knox partisans looking for a convenient villain will not find one in Mignini, who comes off as decent and sincere, a fan of Sherlock Holmes who has a passion for investigating and connecting clues.

But what is also true of Mignini is that he is a practicing Catholic who believes “God runs the world but man has free will,” the father of four girls and a pillar of Perugia’s traditional society.

As such, you can feel in these interviews Mignini’s almost visceral dislike of and even antipathy toward Knox personally — he describes her at one point as “inexplicable, irrational” — and the world of youthful sexual license she seemed to represent.

Mignini and the Perugia police evolve the theory, spread by Pisa and others, that Kercher was killed in a drug-fueled sex game gone wrong and arrest Knox, Sollecito and a third man, Patrick Lumumba, in the crime.

Though both Knox and Sollecito initially protested that they’d been together all night in his apartment, under intense police questioning they temporarily changed their stories. Hearing both of them talk about the almost surreal pressure put on them inevitably brings to mind the coerced confessions that figure in Ken Burns’ “The Central Park Five” documentary.

If possible, things get even more complicated when Lumumba is released and yet another man, Rudy Guede, is arrested. DNA evidence is trumpeted in the trial as being conclusive and eventually seen as tainted (independent Italian experts are among those interviewed here).

It is all so complicated that it took directors Blackhurst and McGinn and editor Matthew Hamachek a full year to fit all their material into the hour and a half on view here, but it was worth the effort. Hard as it is to say that anything is the last word in this most divisive of cases, “Amanda Knox” looks to be it.