Unsolved Child Murder:Shadow Of Truth.

When thirteen year old Tair Rada was found dead in a locked toilet cubicle at her school in Katzrin, Israel in 2006 it was clearly a murder. The knife wounds and the blood smeared walls proved that. But who murdered Tair and what motivation could someone possibly have to murder a schoolgirl? That was much less clear.

Shadow Of Truth (BBC4/iPlayer, directed by Yotam Guendelman and Ari Pines) tells the story of her death and the story of what happened after her death, the search for her killer, and it is a truly bizarre and bewildering story. One that gets stranger and stranger and stranger the longer it goes on.

Despite its grisly subject matter, it doesn't feel exploitative. There's even home video footage of Tair which acts as a reminder that we are watching a documentary about a real person, about a much loved daughter and friend. A documentary that is narrated by, among others, Tair's mother and father, Ilana and Shmuel, her classmates Lee and Nofar, and family neighbour Zvi, as well as countless investigators, private eyes, psychologists. Even the mother and wife of one of the suspects:- Roman Zadorov, a Ukrainian resident in Israel who worked at the school as a handyman.

We're even treated, if that's the right word, to actual footage of some of the police interrogations. Some of which pushes at the edges of legality. Some of which crosses right over. The search for a missing girl turns into a search for a murderer and then it turns into something else entirely. Even when a suspect is arrested, confesses to the crime, and is found guilty of it not once but twice.

Even with the believed murderer in prison, things still don't sit right with some and over five episodes of varying lengths we're taken on a rollercoaster ride that encompasses the predictable media circus and the immediate pressure on police to make an arrest following the murder, a whole town of traumatised and frightened (for their lives) children, psychiatric evaluations, polygraph tests, phoney psychics (is there any other kind?), paedophile websites, rumours of a Satanic cult, BDSM, wrongful imprisonment (I watched a lot of Ludovic Kennedy when I was younger and this is a subject I'm well versed on), imginary elves, and a woman who believes she is possessed by a she-wolf called Mildew.

Ultimately, the crime and the handling of the crime ended up destroying - and in the case of more than one suicide contributing to the ending - of many lives. Even the programme Shadow Of Truth eventually becomes part of the story it seeks to tell. That may all sound hopelessly confusing and endlessly depressing but though it's terribly sad it is constantly enthralling even when the story disturbs and chills.

Which it does often. When Shmuel talks about imagining his daughter's brutal murder and how it was carried out or when a man who has confessed to the murder demonstrates how he did it (even though, it soon turns out, he didn't actually do it). That may sound hard to believe. Why would anyone confess to such a heinous crime if they'd not done it? But people do - and often. Shockingly, in the US over seven hundred people, some on Death Row, have been released from prison after having confessed to murders they hadn't done.

Their innocence having been proven beyond doubt. Their confessions having come after being placed under incredibly heavy stress. I know from grim personal experience how this may work but Shadow Of Truth goes further and shows the machinations and tricks that the police used to force a confession from an innocent man. It'll anger you nearly as much as Tair's brutal murder. Even more so when you realise that this framing leaves the real killer at liberty.

Each episode begins with a thought provoking quote (from the Bible, from Buddha, from Rene Descartes, from Demosthenes, from Ambrose Bierce) and the ominous score c/o Tom Darom and Assa Raviv helps to create a state of suspense that continues right until the very final second. The story twists and turns and takes us in so many unexpected directions, at one point it seems Facebook was used for the common good - though it soon reverted to its more traditional sinister use, and as we look out at a morally bankrupt world, a world in which distrust of experts is weaponised and powerful establishment figures close ranks to protect their interests, we hope for some justice or at least some redemption. But will we get it? You'll have to watch it yourself to find out and I highly recommend you do.