And I transform the Creeper into an ugly shoe: specifically, a size-six loafer with tassels, used. I turn to catch Melodie’s reaction, already thinking how gracious I’ll be when I decline the bonus she’s going to offer me – and the man-form of the Creeper is standing over her again.

‘Charlie, help!’ Mel squeaks.

‘You’re an amateur,’ the Creeper tells me. ‘Is that really the best you can do?’

Melodie has slid off the stool and is edging towards the side curtain at the back of the stage. I’m aware of her, but I don’t let myself look her way because I’m busy getting up in the Creeper’s face. I kick it in the shins, and it laughs.

I throw the contents of the dustpan at it. Dust and finger bones come flying out, and scraps of dried skin hang in the air like tiny parachutes. A shrivelled-up eyeball bounces off the mask. Now the Creeper’s mad. I can tell. The mask quivers with rage.

Melodie slips through the curtain.

‘You’re an idiot,’ says the Creeper and disappears.

My heart is racing. I look around the empty theatre. Where did it go? How did it do that? If the Creeper is just a psychological complex, it sure is a slick one. It’s not acting like it’s out to get Mel half as much as it’s out to upstage me.

I run backstage, calling Mel. It’s a maze of passageways, and the farther I go the more I see body parts lying around on the floor. At first I think they’re stage props, but there is a smell, too. It’s nothing like Mrs Haugh-Wombaur’s farts. It’s primitive, blood and faeces and fear.

I find the orchestra’s dressing room. There’s another door inside, left ajar. Cold, fresh air comes in from outside. I open it expecting a fire exit, but when I step out I find myself on a scaffold. I reel to a stop, grabbing a support pole.

Somehow we’ve got somewhere very high up. Higher than any theatre, higher than the hotel where Mel dreams. Higher than anything in London; but I shouldn’t be surprised, because we’re not in London any more. This is the Dream City for sure. I’m nervous to find myself here while responsible for a client. I guess there’s a first time for everything.

I need to be careful now. The Dream City’s a tricksy place. Must orientate myself. I look around, straining my senses for some hint of where Mel has got to. The scaffold looks down on a neon-lit flyover with cars spooling silently across it, and below that a network of canals and lesser buildings sprawls. The skyline is aggressively broken by the silhouettes of cranes, like praying mantises.

‘Mel?’

Where has she got to? What is this place? If it’s really some kind of collective entity, then who built it? And where is it really located?

What’s hardest of all to describe about the Dream City is the way it takes hold of your imagination. I know I should be looking for Mel but I’m distracted by the architecture. I see gardens set on the sides of buildings. I see hang-gliders drifting in slow spirals from the highest towers towards the water below. I see tiny windows all lit up. There must be millions of people here.