He examined the LP’s cover, one of those Seventies group-picture photo shoots that looked as though it had taken all of five minutes. The band hadn’t even bothered to put Angus Young in the schoolboy uniform he wore on stage, although Angus was the only one who had made a modest effort, wearing a pair of plastic devil horns, the kind you might see worn on a hen night in Blackpool. Only Bon Scott, the singer, had a grin on his face. Bon Scott, who would be dead within the year. The rest of the band stared sullenly out from under their mousey mullets. I felt a surge of love for AC/DC, and for Spike.

‘Best Australian band ever,’ I said. ‘And that’s their best record, released in 1979. Their breakout LP. But genius might be very slightly overstating it.’

‘Are they Australian?’ Spike said, examining the record. ‘I never knew. But it’s genius, as I say.’

I had missed him.

And I had missed all of this – a drink with friends, talking about music – even if my friend was talking rubbish about music. He began singing – or rather, he began impersonating the opening riff to the title track.

‘DER! DER! DER!’

It was more than a joy to see him. It was a relief. From the moment Tara came home from Tokyo, there had been so many tears. Seeing my friend slightly drunk while he talked about AC/DC made me smile again.

‘It’s really good,’ I said. ‘It’s great, even. I love AC/DC too. But genius? It’s all pretty simple. That opening riff?’

‘Great riff! DER! DER! DER!’

‘Spike, I could teach you to play that guitar riff in half an hour. It’s just three open chords.’

‘Yeah, and when we’ve done that you can show me how to run like Usain Bolt or paint like Picasso.’

‘No, it’s simple! Let me show you.’

I fetched my old Fender Telecaster and a little 15-watt practice amp. I strapped it on Spike and showed him how to arrange three fingers into an open A major. I gave him a light pick.

He shrugged his shoulders, surprised at the weight of the Fender.

‘You hit that A chord three times, very fast, and then – very quickly – you mute the strings by placing your palm on them. Press down the meat of your hand. That stops the chord ringing out and you get that great dynamic crunching sound. DER DER DER – mute – then silence.’

He hit the strings too hard, including the thick E string, which he was meant to miss, and the little practice amp howled discordant metal feedback.

We fell about laughing, Buddy barking, tail wagging like windscreen washers, Marlon covered his ears, laughing wildly, overexcited and up way past his bedtime.

Then we saw Tara and Ginger standing in the doorway, staring at us without expression, and our laughter immediately faded.

‘It’s your turn tonight, Spike,’ Tara said.

Spike chose Argentinian.

Groans.