He dialled Laura’s number. But inside the club the music was too loud for anyone to hear their mobile phone.

At 11.00 pm Stephen O’Brien brought a trayful of tequila slammers to the table that the Dalkey gang had found. Everyone knocked one back. They licked the salt and bit the wedge of lemon.

Laura went to the bathroom to reapply her lipgloss. In the cubicle she took her daily dose of Lexapro. You weren’t supposed to drink while you were taking Lexapro but Laura had flouted this rule often enough to know that she would probably be alright.

Out on the seething dance floor, Stephen O’Brien looked at his phone and saw that there were seven missed calls, all from Richard’s number. He went outside and found Richard sitting on his bench.

‘This is fucking ridiculous, Steve-o,’ Richard said. ‘I mean, what’s the fucking story, like?’

In Stephen’s opinion (stated at the trial), Richard was not noticeably drunk at this time.

‘Keep your knickers on,’ Stephen said. ‘We’ll only stay for a few, alright?’

‘I might as well just hit the road, like,’ Richard said.

‘No, no,’ Stephen said. ‘Look, I’ll fucking smuggle you out some hooch, alright?’

‘Send out Laura,’ Richard said.

‘Will do,’ Stephen said.

He went inside and came back fifteen minutes later with a hip flask of cognac concealed in his hoodie. He passed it to Richard.

‘Christ, man,’ Stephen said, ‘Half of St Anne’s Sixth Year is in there. It’s like fish in a barrel.’

‘Fuck off,’ Richard said. He drank from the hip flask. ‘Where’d you get this?’

‘Got it off Whelehan,’ Stephen said. ‘He never leaves home without it.’

‘Where’s Laura?’

‘Dunno, man. I’ll send her out, yeah?’

Stephen O’Brien went back into Harry’s. Richard sat on his bench, drinking from Dave Whelehan’s hip flask. He began to smoke some cigarettes of Laura’s that he had found in his jacket pocket.

At 11.50 pm Clodagh Finnegan limped over to Stephen O’Brien, complaining that some bitch wearing stiletto heels had accidentally stood on her big toe. Gallantly Stephen knelt to kiss the big toe better. Then he and Clodagh went outside for a smoke. For five minutes or so they kept Richard Culhane company.

By now Richard had, in the words of the prosecution, ‘become aggressive’. He shouted at Stephen for not finding Laura. The truth was that Stephen kept forgetting about Richard and Laura. In his own words, he was by this time ‘fairly stocious’. He too became aggressive. He told Richard to fuck off and brought Clodagh back inside.

At 12.02 pm Fergal Morrison left Harry’s and took Joanna Carruthers home in a taxi.

At 1.04 am Lisa McKeown complained of feeling sick and called her father, who arrived to take her home twenty minutes later.

Conor was now alone in the club.

This is where accounts start to break down. By one o’clock in the morning, everyone was drunk or stoned or scoring. Or they were otherwise engaged – with drug deals, with rivalries, with getting home safe. People’s recollections about this part of the night tend to lack clarity. They tend to contradict one another. We know so little. Even after a garda investigation and a trial, even after exhaustive conversations, we know so very little about the things that happened next.