We swerved round the mini-roundabout on Long-acre, slowed in deference to another crowd of drinkers outside the Kemble’s Head on the corner and accelerated down Bow Street. I couldn’t see any police cars, fire engines or other signs of an emergency outside the Opera House, so I figured we might have got there in time. Beverley pulled into a disabled parking space opposite the Opera House.

‘Keep the motor running,’ I said as I got out. I wasn’t really anticipating a fast getaway but I figured it would keep her in the car and out of trouble. ‘If the police try to move you on, give them my name and say I’m inside on official business.’

‘Because of course that’ll work,’ said Beverley, but she stayed in the Mini which was the main thing. I trotted across the road to the main entrance and pushed through one of the glass and mahogany doors. The interior atrium was cool and dark after the sunlight; manikins were mounted in glass cases by the doors, decked out in costumes from previous performances. As I went through the second, interior set of doors into the lobby I was met by a sudden rush of people coming the other way. I looked quickly about to see what could be driving them but, although they were moving briskly and with a sense of urgency, there wasn’t any panic. Then I twigged: it was the interval, and these were the smokers heading outside for a cigarette.

Sure enough, there were crowds of people streaming out of the doors marked stalls and heading left, presumably towards the loos and the bar – probably in that order. I stayed where I was and let the people go past – Seawoll at least, because of the sheer size of the man, should be easy to spot. Sartorially I was disappointed; everyone was dressed expensively but it was all smart casual with the occasional evening dress to relieve the boredom – I’d expected better of my betters. The crowd thinned and I merged with the flow and let it carry me left, past the cloakroom and up a flight of stairs into the main bar. According to the sign this was the Balconies Restaurant, and as far as I could see had been created by throwing several metric tons of stripped pine into a Victorian cast-iron greenhouse. Designed to serve the interval crowd, when a thousand lightly stunned punters would rush in and attempt to drown out the singing with gin and tonics, it featured large open spaces and plain padded furniture with clean brass fittings. Under the vaulted arch of its white iron and glass roof it was as if IKEA had been hired to refit St Pancras Station. If Thomas the Tank Engine had been Swedish, then his living room would have looked just like this.

Although he probably would have been a lot less cheerful.