I creep down the stairs, which are lined with photos of Alice and people who are presumably members of Alice’s family, and as I catch another glimpse of the street outside, I realise I have absolutely no idea where I am. Am I even still in London?

I check Google Maps on my trusty iPhone 13 to find that I’m currently in Hammersmith. Only a few miles from Daff’s and my flat in Kensal Rise.

Which, surely, is no longer Daff’s and my flat …

Panic ripples through me again. Is she there now? What is she doing?

I get the sudden urge to call her, but I’m instantly distracted from this idea by the sight of my reflection in the hallway mirror. I actually have to stop myself letting out an audible gasp as I see it. If the outside world appears unchanged, the same can definitely not be said for my face.

My hair has shuffled a good quarter-inch backwards on my forehead, and I’m sporting new wrinkles in places I didn’t even know you could get them: the side of my nose, for instance. The patches of grey at my temples have extended their territory significantly, and most disturbingly, my eyebrow hair has taken on a vaguely owlish quality. A couple of strands are so long that they could almost be stretched out to meet my retreating hairline.

I am thirty-seven years old, and I very much look it.

I run a hand over my face. The world feels less real than it’s ever felt, but it doesn’t change the fact that this could be it: I could very well be back in reality right now. The thought makes my stomach flip. And then, from down the hall, I hear:

‘Ben, come on! Breakfast!’

I tear myself away from my thirty-seven-year-old reflection and follow the sound of clinking plates down the corridor. As I push open the kitchen door, I see Alice at the counter, her back turned to me, pouring almond milk into a bowl of something that looks like it should be lining the floor of a hamster cage.

‘Hey, you,’ she says, without turning round. ‘How are you feeling now?’

‘Yeah, I’m—’

‘Don’t be ill, Ben, seriously,’ she says, cutting me off. ‘Not on Christmas Day. I want you on good form today, charming the pants off everyone.’

She spins around, holding the bowl of moist sawdust out to me, and prods me three times in the stomach: ‘Don’t. Be. Ill!’ She’s smiling, but her teeth are clenched, and those stomach prods were definitely straddling the border between playful and aggressive. Is she pretending to be annoyed, or is she actually annoyed? It’s very hard to tell.

‘OK?’ she adds.

I nod. ‘Yep. OK … No, I feel better already, actually.’