‘Of course!’ She picks up her phone and taps out a message.

‘There! I’ve told Trevor you’ve talked me into staying in.

I’ll have an early night.’ She leans over and kisses the top of my head.

‘Please don’t fret. I’m here whenever you need me, including over the holidays.

I hate the thought of you being on your own.

You must join me and Trevor’s family for Christmas lunch. ’

‘I’d love that, thank you!’ The tension dissolves from my shoulders as we embrace tightly.

I’ve made certain she’ll be here on 25 December, haven’t I?

My close connection with her must have saved her life.

Joan breaks apart first. ‘You should get a move on – the roads might flood, and the buses will be bad.’

I hesitate. Ideally, I’d stay until shortly after midnight to make sure she’s safe, but I can’t ask to sleep here. That might freak her out. I should return to my bedsit.

‘I’ll listen to the radio in bed and mend clothes – nothing risky,’ Joan says, as if reading my mind. ‘Why don’t you come back next weekend? We’ll carry on making Trevor’s log cabin quilt – take this section, to practise your stitching. I’m including Chester!’

‘Great!’ I take the green fabric, which has a printed picture of her son’s rough collie in the centre. Yellow and brown strips of material are pinned around it.

I follow her into the hall and pull on my anorak, scooping up my rucksack.

She kisses my cheek. ‘Thank you for being such a caring friend.’

‘You too!’

Wind blows in a funnel of water as she opens the door, spraying the floor. I step out and wrestle to keep my hood up in the gale.

‘Remember to turn off your Christmas tree lights,’ I shout before she disappears inside.

I pelt down the path, triggering a security light fixed above next-door’s porch.

It illuminates a skip on the drive, which contains a sink, kitchen cabinets and an old gas boiler.

My socks are sodden within seconds. Further along the flooded pavement, the tree groans in warning, but I don’t slow or stop.

I try not to worry about how many days I have left.

Staring in mirrors has never revealed a glimpse of my number; the date of my death is a mystery.

I pass beneath the sagging branch and increase my pace.

Three seconds later, a loud splintering sound reverberates.

I spin around as 152 kilograms of timber smashes on to the pavement.

Yes!

I punch the air with joy. Joan would have been crushed to death if she’d walked beneath it.

Our friendship has saved her life. I shove my hands into my pockets, searching for my gloves, and feel something rectangular and stiff.

I pull out Joan’s bus pass – I’ve accidentally picked it up.

I hurry back to stick it through her letterbox, my heart light.

Suddenly, a huge explosion booms, setting off car alarms. Bricks and debris pelt on to the road with heavy thuds.

Someone screams. My ears ring and numbers swirl treacherously in front of me like a swarm of poisonous insects.

I run blindly towards the deathly sounds, tripping and stumbling until I reach number 40.

Breath is squeezed from my lungs and my blood turns to ice. Joan’s house is no longer standing, and neither is her next-door neighbour’s. Both homes are reduced to piles of rubble. Flames lap hungrily over the shells of the buildings, and smoke spirals high into the sky.

People run from nearby houses towards the carnage.

‘Someone ring the fire brigade!’ a man yells.

I’m frozen to the spot, unable to pull out my phone. I can’t tear my gaze from the charcoaled carcass of Joan’s house; the wreckage is unsurvivable.

‘Crews are on their way,’ a woman calls back. ‘The operator’s asking if anyone could be inside the houses?’

An older female voice pipes up. ‘Joan’s usually at bingo tonight, but the weather may have kept her indoors.’

‘Steve’s taking his wife out for dinner to celebrate their anniversary,’ a man adds.

‘They wanted to get away from the building work – they’re having their kitchen refitted.

’ He pauses. ‘Oh God! The force of the explosion... Nothing else could bring down two houses like this apart from a ruptured gas pipe.’

My knees give way and I sink to the pavement as I remember the boiler in the neighbour’s skip. I hadn’t registered the danger lurking in plain sight. I slump on to my side. I don’t feel the slick wetness of the concrete against my cheek, or through my clothes; I can’t feel anything at all.

‘I think she’s gone into shock,’ someone cries.

‘Joan,’ I whisper.

‘What was that?’ A young woman crouches beside me. ‘You think Joan’s home?’

I nod and close my eyes. I’ve failed again. I’m responsible for the death of my friend and everyone else I’ve tried to help. Lily’s fatal injuries last summer were all my fault.

Blinding lights, smashing glass and ripping metal.

I want to rewind the numbers to the days before that awful prom night and replay them in a new order that saves Lily, Mum, Joan and all those strangers.

It will take me back to Adam, to the life we could have had together.

But deep down I know I’ll never find the magic formula for love and happiness. I don’t deserve either.

Emergency sirens whine in the distance.

‘ Sorry, sorry, sorry. ’

I repeat the words in between ragged breaths as the fire engines draw closer.

‘It’s not your fault,’ the woman says reassuringly.

I peel open my eyelids and see a concerned face – and another low number.

An anguished howl pierces my eardrums. It sounds like someone in unimaginable pain.

It takes a few seconds before I realise the cry is coming from my lips.

I press the heels of my hands into my eye sockets to try to block out her lonely, single digit.

‘I can’t do this anymore,’ I scream. ‘I want it to stop. Please make it stop!’

‘Stop what?’ she asks.

‘The numbers! They won’t stop counting down.’

‘What numbers? How do you mean?’

I can’t help anyone. It’s futile. If I try to change the course of things, fate always intervenes and finds a way.

I give up.

I’ll never attempt to save another person’s life, however much I love them.