WE begin, fittingly, with an exhumation. A cold February in 1996, Stonehouse, Lanarkshire. A white plastic tent sits amongst the graves; you can hear the buzz of pneumatic drills at work on the frozen ground.

Forensic pathologists want bone tissue from a local, one John McInnes. The scientists, the police, the press, and the public want the answer to a burning question: is this Bible John?

Why the fascination with a series of unsolved murders from the late 1960s? This is Francisco Garcia’s subject. He knows we know that no-one knows who Bible John was; that the tests on McInnes were inconclusive; that other noxious criminals from the past (Fred West, Peter Tobin) have been excluded; that there may be no single killer. As Garcia admits, the story is “a litany of false starts and dead ends”.

Living in London but calling Glasgow home, Garcia notes the “tolerant incomprehension” when he talks to Southerners of his obsession.

He’s surely right to say: “Bible John means something different here.” But what? Something grim and Grimm-like, a bogeyman to frighten the children.

I remember John well as a kid – that artist’s impression, the photofit that could be anyone, his normative anonymity an existential threat.

Your mum’s voice, Tufty the squirrel’s voice: Stay away from strangers.

Garcia is honest about his own “strain of morbid curiosity” and admits he’s not trying to solve the crime. He wants to make sense of what the story means. His approach, his method – interviewing many who have written and thought about the case – recalls Ron Rosenbaum’s extraordinary Explaining Hitler. Get up close to those who have been near evil and listen.

The book is about evil acts and how we want a rational explanation, even if this isn’t apparent.

Like inter-war Germany, we are in a world of cruelty, of poverty, of vicious violence. We might imagine the killer as depicted by George Grosz: see his John, the Sex Murderer from 1918.

Garcia paints 1960s Gallowgate like it was a later variant of the Weimar Republic.

He has little time for romantic nostalgists hymning the Barrowlands – this is haunted ground.

On lonely dark and wet nights, you still feel the low hum of evil. Stevenson’s Mr Hyde would feel at home here – the Calton as the epicentre of Scottish antisyzygy – our dual nature.

See Bible John (“well-spoken, well-dressed”) as James Hogg’s justified sinner, quoting scripture.

This is material ripe for dramatisation, for taking Capote-style liberties with the verité, but Garcia is alert to the lurid risks of mere voyeurism. Like Gordon Burn, he trusts the facts, the details, and studs his narrative with vivid snapshots of the real as with an all-time-classic LOL graffito referencing the old hoofer, Frankie Vaughan.

GARCIA doesn’t flatter his hometown. He stays at an Ibis Budget hotel in a “baleful retail park”, a “battered B&B at the top of Garnethill”, visits a dreich Lambhill Cemetery, and notes Glasgow’s “increasingly depressed centre”. Home truths… The bad news piles up – the crime reporter Jane Hamilton admits the public “hoover up true crime” and thinks our Bible John fetish tells us: “Probably not what people want to hear … we are a very parochial nation.”

The forensic pathologist Marie Cassidy says that even when Glasgow was the European City of Culture she was “extremely busy”.

Garcia’s book is about the void of uncertainty, about the slipperiness of facts. And spooky coincidences too: a sports reporter called John Quinn (yikes!) apparently coined the name “Bible John”.

It’s a tale with false names and false pasts – in Garcia’s own words about another volume, it’s “an awkward, discomforting thing”.

As literary exhumation, the book may trigger bad memories – for me, a man with a fake name and fake chest pain who punched a nurse. Could that have been Peter Tobin?

Garcia reminds us Tobin had a history of being nastily duplicitous in hospitals… Like Friedrich Dürrenmatt’s The Pledge, Garcia’s book can be read as a kind of requiem for the (true) crime novel.

There’s no resolution here. There’s no healing for the relatives of the victims. The case is a keloid scar, a hypertrophied disfigurement, that won’t go away.

And it reminds us, scarily, that there’s murderers among us.