The crime itself is awful, but this shouldn't have needed to be more than 60 minutes in length. Any true crime fans who've ever watched any episode of Snapped or Obsession: Dark Desires (et al.) will not likely view this story as having any "twists or turns". The outcome will be evident within the first 5 minutes, making it a pretty long ride if you already know what's going to come from the set-up. If you don't know many true crime stories at all, it may be interesting to you, but unfortunately, it is an all-too-common story of cops not following up on anything, and making a case last years longer than it needs to.
Also if you were born before 1980 you may recognize the near constant "spooky whistling" (as the captions referred to it) as the Lassie theme song. Kind of distracting when trying to take something seriously. There are also weird filmmaking continuity errors, such as the subject stating that he left his apartment looking for apartment 12, but then shows him living in apartment 12 in the next scene -- which isn't possible as apartment 12 didn't exist.
Despite the filmmakers not knowing wtf they are doing, there are still one or two important takeaways if you don't already watch a ton of true crime.