In February 1970 Green Beret doctor Jeffrey MacDonald’s pregnant wife and two daughters were found brutally murdered in their home. MacDonald claimed that a gang of hippies, led by a blonde woman in a floppy hat, entered his house and killed everyone. It made sense right away, particularly as the Manson family killings took place just six months before. But as “A Wilderness of Error,” produced by Blumhouse television and airing on FX, asserts, that is just where the story begins.

Director Marc Smerling is best known as a producer on the runaway true crime documentary “The Jinx,” which, like “A Wilderness of Error,” simultaneously explores the crime and the way documentaries construct narrative. That former feature was later accused of dramatizing and playing with facts in a way that could be detrimental, so Smerling and crew confront that head-on. Morris, whose book on the MacDonald case gives this documentary its name, sets things in motion by discussing how it was a narrative — in this case the 1984 made-for-TV feature “Fatal Vision” —  that did more to convict MacDonald than any actual trial. It’s a concept that’s executed so breathlessly throughout the miniseries’ five episodes as the documentary actively causes the audience to question what is being presented. Case in point, the woman in the floppy hat. The first episode admits that, yes, there was a woman known to walk around the city of Fayetteville, North Carolina who wore a blonde wig and had a floppy hat. In fact, said woman, Helena Stoekley, confessed to several people that she was in the MacDonald home. Yet as events unfold, nearly every fact becomes challenged. Smerling doesn’t just put Morris’ own opinion in the hotseat — Morris says at one point that he believes MacDonald is innocent as if he’s adding a question mark at the end — but the concept of true crime itself in the spotlight. What makes someone believable? Does the fact that people know the statistics about husbands murdering wives and family alter our perception? More importantly, does a cinematic or television depiction of events serve as a proper recreation, or is it entertainment? FX

With that, Smerling doesn’t present a specific theory. Instead, he presents every theory, from Morris’ contention that Stoekley had to have some involvement to the prosecutors’ belief that MacDonald acted alone. And within those theories there are added layers. If Stoekley was involved, was there evidence suppressed by the prosecutors? If she wasn’t involved, was the trial against MacDonald fair? At times it often feels like certain players are so desperate to declare MacDonald innocent they’ll do anything, but shouldn’t they? It goes to the heart of the justice system, asking why our natural inclination tends to be guilt first. Of course, there is a penchant to question — particularly in these times — whether the goal of “A Wilderness of Error” is to prove that MacDonald is a lone man wronged by the system in a witch hunt. But Smerling is actually remarkably deferential. The series doesn’t get lost in the weeds of deconstructing every little thing or giving a point-of-view. In fact, this is one documentary that, at just five episodes, feels like there needs to be more information, and that can be frustrating. Either this is the simplest, cut-and-dry case in judicial history or there’s something more. But what if it is just the former? The fact that a true crime documentary can bring up these questions is amazing as the genre often is only there to upend preconceived theories. The lack of resolution may astound audiences who demand catharsis, but it is that very impetus to have the audience question the nature of narrative that keeps “A Wilderness of Error” lingering in the mind long after its five episodes have concluded. And it’s great fun to watch Morris squirm as Smerling starts to point at facts that may make the acclaimed “Thin Blue Line” director question everything he knows. “A Wilderness of Error” is a new kind of true documentary that will keep you on the edge of your seat and eager for more information. It’ll be easy to see people clambering to read Morris’ book as well as “Fatal Vision” after this. If you missed the can’t miss quality of “The Jinx,” this will fill the void.

Grade: B+

“A Wilderness of Error” premieres September 25 on FX. Sign Up: Stay on top of the latest breaking film and TV news! Sign up for our Email Newsletters here.