It is blue. Like the sky stretched over a Greek island in mid-summer, like a tropical sea, like the shell of a duck’s egg. It is blue like the thin vein that marks the pale skin stretched taut around the bicep of the guy sitting opposite me as he leans forward in his seat, a book held lightly in his perfect hands.

It is impossible to see what he is reading without craning forward, without making it obvious I am staring.  I drag my eyes from his hands, up his arm again, to his face that is fixed in concentration – biting his lip, pale blue eyes running over the pages rapidly, devouring the words. I fall in love as we thunder through the tunnel from Green Park to Oxford Circus.

Blue, like a tunnel through the sea. Like the hottest part of a gas flame, like the swimming trunks you owned as a kid and wore every beach holiday for years. By the time we reach Warren Street my heart has started beating faster and I can feel a prickling along the nape of my neck. As I try not to look at him, I am hyperaware of the space around me – of the enormous man sitting next to me, whose shoulders rise at least half a foot higher than mine, his thighs as wide as my waist, the press of his body against me; of the older couple wearing matching fleece zip-ups, looking nervous about being on the tube; of the two young girls sitting next to me looking at their phones, showing their screens to each other and giggling. A Sunday afternoon crowd.

Kings Cross station looms above as we pass beneath it – the crowds of people heading north, the great blue barn of St Pancras station, an industrial marvel, a metal-blue sky tacked onto the back of the giant hotel. I grip the tote bag on my lap.

Close my eyes and count down from ten. Steel myself and take out my own book – determined to concentrate on something else.

But now he is young. Not a thread, not a sheet of paper lies between him and the sun, between him and the rain, between him and the moon as he lies naked, tumbled, hot, on his bed.

Look up. He is looking at me. Here, in the big gap between Kings Cross and Highbury, in the void that seems to stretch on forever, he looks at me and lifts the book in his hands to show me the cover. The walls of the tunnel flash by inches from the skin of the carriage as I see The Waves and I smile, embarrassed to be caught looking.

It begins to feel like we could be on this train forever, as if we are destined to stay here forever – an infinite hurtle through the darkness lit by overhead florescent lights. People sway where they stand. No one speaks. I hold Woolf in one hand and my bag rests on the floor between my legs. It carries wine and chocolate for the party – a gift, a pre-emptive thank you for having me, a desperate offering.

I am in love.

It seems impossible that we will ever arrive and that this roaring silence, this wave of noise and shuttering light and darkness and gentle rocking to and fro will ever end, that his eyes will leave mine and in the new dawn of the harsh station light a small moment of magic, of exchange, will fade. Determined to hang on to it I don’t look away and, instead, show him the cover my own copy and mime that I am deeply confused by it, even though I am not. He almost laughs and then rolls his eyes.

And then, like the breaking of a wave, like dawn cantering over the horizon, like someone has flicked on the switch in your bedroom and brought on the lights to wake you from a dream with a start, we erupt from the tunnel into the station. I look back and he has looked away now, is gathering his things.

He stands, picks his bag from the floor of the train, still gripping the book in his hand. I think, for a second, that I should speak to him, say something, say anything, blurt out – You’re fucking beautiful, do you know that? – and damn the consequences. But I don’t.

I watch him stand at the doors, waiting for them to open, and I try to memorise his shape – the curves of his legs, the way his hands hold his things – and then, pressing through the waiting crowd to get off, he is gone.

I sit for a second. I feel the tide slowly going out. Blue like the deepest ocean, like an empty swimming pool at the height of summer, like cold, hard stone.

And then, I am up. Out between the doors just as they start beeping at me, just as they slam behind me and I see him, at the end of the platform, heading for the way out. Swivel through the crowds, ducking and diving. I run up the stairs and then charging up the left hand side of the escalator to reach him. And I arrive panting and sweating and stand in front of him as we move up towards the surface.

I start speaking.

I. I know this is super weird, and I, well, you’re probably straight, but…do you want to go to a party with me?