‘Are you kidding?’ Step said. ‘You got me out of the world’s longest Peppa Pig marathon.’ He added, more seriously, ‘And I’m happy to do anything I can to help. Alex was the closest thing I ever had to a best friend.’

Lightman thanked him. ‘There are a few things we need to ask you. The first is whether you saw Alex with a woman on Friday.’

There was a long pause, and then Step said, ‘I’m sorry. I should have said before. Karen – my wife – was angry with me for not telling you about it. I just … Yes, I did see Alex with someone.’ There was an audible swallowing noise down the line. ‘There was a woman who was – well, she was hitting on him quite hard. And – he ended up kissing her.’

‘Why didn’t you mention this before?’

‘Because it happened much earlier on,’ Step said. ‘A long time before I left. And he clearly immediately regretted it. He backed off, and she was angry with him about it. I actually had to get involved, to try and calm things down.’

There was a note of defensiveness in his voice, one that was possibly understandable in the circumstances.

‘She felt rejected?’ Lightman asked.

‘Yes.’

‘How did she react after you talked to her?’

‘She calmed down after a few minutes,’ Step said. ‘I think she was just drunk, you know? Anyway, she left him alone after that. I saw her talking to another couple of guys before I left, and she looked like she was having fun.’

‘I’m going to share a photo with you,’ Lightman said. ‘If that’s OK. A woman we know to have been at the club. Do you have your mobile on you?’

‘Yes, I can look now,’ Step offered.

He waited in silence as Lightman forwarded both the arrest photograph of Louise Reakes, and then another image of her captured from the CCTV. He heard a faint chime in the background as they arrived on Step’s phone.

‘Can you let me know if that’s the woman Alex kissed?’

There was a brief silence, and then Step said, ‘No, it wasn’t her. Sorry.’

Lightman found himself momentarily at a loss. Given everything that happened later that night, how could it possibly have been anyone other than Louise Reakes?

‘That’s fine,’ he said, as smoothly as he could. ‘Could you describe the woman you saw him with, perhaps?’

‘Sure,’ he said. ‘She was pretty noticeable. Blonde. Really tall in her heels. She had tattoos. One across her chest and another one on the small of her back.’ He looked away for a moment. ‘Oh, and she was American. Southern. Really, really hard to understand.’

‘Thank you,’ Lightman said. ‘I think we know who that is.’