When BBC Two aired The Investigation earlier this year, it seemed to herald a brand new way of approaching TV crime shows. Based on the true-life murder of Swedish journalist Kim Wall in 2017 at the hands of a vicious inventor named Peter Madsen, this Nordic Noir chose never to mention the killer's name. Not only that, but it stridently veered away from classic crime-drama tropes such as the tense interrogation scene or the lightbulb moment when all the pieces fall into place while an investigator stares hard into the middle distance.

This latest Storyville documentary, the feature-length Raising a School Shooter opts for a similar outlook. In films such as these, the soundtrack would normally feature spine-chilling background music, as well as pictures of victims or perpetrators usually looking happy in family photographs. There might even be video footage of them. Given that one of the three tragedies revisited here is the 1999 Columbine High massacre after which the media got its hands on CCTV film of the heavily-armed killers stalking the school canteen while their peers attempt to flee in terror, a clear decision was made by the filmmakers to completely avoid such sensationalism.

This wholly dignified film focuses on three American parents who woke up into a perfectly normal day and went to bed that night knowing that their child had committed an appalling crime. We meet Sue Klebold (mother of Dylan, one of the two Columbine shooters who killed themselves after their murderous spree), Jeff Williams (whose son Andy is serving life after killing two classmates in 2001), and Clarence Elliot (his boy Nicholas is unlikely to ever walk free again after gunning down a teacher in 1988).

We follow the trio doing everyday things, while the pain and guilt are etched upon their faces. No doubt some viewers will be appalled that these killers' parents are given airtime, but in a gun-crazed society such as the USA, many different kinds of victims are left in its bullet-strewn wake.

BBC Four, Wednesday 7 July, 10pm.