They were, above all, ordinary people enjoying a night out. The youngest were teenagers; the oldest was fifty. Among the dead were two members of the band Trinity, who had been playing that night - Colin Folster, nineteen, and Darcy Day, twenty-two - along with three members of the club's staff and ten patrons. They died of carbon monoxide poisoning, overcome before the firefighters could reach them. In the records of the case, the victims are sometimes reduced to a number, fifteen, or to the legal shorthand of a single charge. But each was a person with a family and a future: musicians mid-set, friends sharing a table, workers finishing a shift. The proper way to remember the Whiskey Au Go Go is to remember them, not the men who killed them.

The horror of the fire is sharpened by how plainly it was foretold. In the months beforehand, the career criminal John Andrew Stuart had spread word of a supposed extortion racket - southern gangsters, he claimed, who meant to firebomb Brisbane nightclubs. He told a newspaper reporter, Brian Bolton, something chillingly specific: that one empty club would be burned first, and then a second, the Whiskey Au Go Go, would be set alight when it was full of people. Bolton wrote about the threat repeatedly and personally alerted the police commissioner and the police minister. Then, on 25 February 1973, an empty club called Torino's was destroyed by arson - exactly as predicted. Eleven days later, the second half of the warning came true, and fifteen people paid for the fact that nobody had stopped it.

The club has since been described, bluntly, as a deathtrap. The single escape route was a set of rear stairs - poorly signposted, cluttered with crates of bottles, opening onto a side alley blocked by a fence nearly two metres high. Some patrons survived only by smashing windows and jumping onto an awning, then dropping several metres to the ground; others scrambled out through the changing-room windows. The path to safety was slick underfoot, and a persistent rumour held that the arsonists had deliberately greased it. That rumour is false. The club simply stacked its used cooking-oil tins against the wall along the escape route, and in the panicked stampede the tins were knocked over and their contents spread by the feet of people fleeing for their lives. The danger was not sabotage; it was neglect, the everyday carelessness of a place never built to be left in a hurry.

Two men, John Stuart and James Finch, were convicted in October 1973 and sentenced to life imprisonment; the jury found the fire had been lit as part of an extortion campaign against the city's nightclub operators. Stuart never left prison alive, dying in Boggo Road Gaol in 1979. Finch was released in 1988 and deported to England, where he confessed to a newspaper that he had poured the petrol - then later recanted, and the case has been argued over ever since. Doubts about whether the right men, or all the men, were caught never fully settled, and in 2017 the Queensland government reopened the coronial inquest into the deaths. The legal threads still tangle decades on. But beneath the appeals and the arguments lies the plain fact the city has carried for half a century: fifteen people went out one night in Fortitude Valley and never came home.