As soon as I consult the office calendar, I'm reminded it's going to be a long day. The first appointment is Fenton's, which is in itself fine, but the one after is Mr Abley. There's a reason I didn't get the files down yesterday in advance, and it's called denial. If I'd wanted a life of thrilling adventure, I wouldn't be working as the secretary and office manager to a small local solicitor.

Leaving a note on the boss's desk to the effect that I'll be in the storeroom, in case he turns up before I return, I head on up. I wonder idly whether it's time for one of my periodical memos about insufficient storage space and inadequate equipment.

I'd like to say I navigate the racks of shelving in our cramped attic with the unruffled composure of the girl with her pushy ladder thing off the old BBC4 ident. The sad reality is that I have to risk an old stepladder which is not quite tall enough, and balance insecurely against the old metal racks – and I can reassure any doubters that it is a lot harder to pull off in a short skirt than Pushy-Ladder Girl makes it look. The problem is particularly acute if it's a client at the beginning of the alphabet because they're on the top shelf and I'm a short-arse.

Miraculously, the whole teetering edifice has never yet – in the dozen or so years I've been there – actually given way catastrophically. But there's a first time for everything, right?

With baited breath, I slide out Mr Abley's file and wait for its neighbours to shift dangerously into the gap created.

Nothing.

Breathing out with cautious relief, I balance the file on the top step of the ladder and twist awkwardly to my right to pull the Fenton's file out from the next shelf down. There's a slight tremor among its comrades either side, but maybe their hearts aren't in it today and they settle down after a moment. Twisting back to gather the two files together, I feel a tug on my cardigan and realise that one of the buttons has got caught in a socket in the shelving unit.

What follows unfolds for me in beautifully-poised slow motion, but I expect the reality is somewhat clumsier.

By trying to compensate for the stretch in my cardigan, I lean forward too far and bang my knee on a shelf. Which destabilises the step ladder. As it begins to wobble, I also knock the side of the racking with my elbow, and this duly angers the precariously-balanced files, which decide to come out fighting. Mrs Burton's takes the lead, skimming my hair and dislodging the clasp; Mr Carpenter's follows, but I manage to duck him, only to be struck a glancing blow on the temple by Armitage & Sons darting in on the opposite flank. Several files from lower shelves make bids for freedom, further destabilising the stepladder where they tumble around it. My glasses tangle in my newly-freed hair, my foot slips on the step, and the tension becomes too much for my cardigan to bear – severing it from the still-caught button and releasing me from my single, flimsy anchor point.

I am perfectly free to tip backwards into thin air.

Luckily, the caretaker of the shared building has recently been re-lining the attic and I land on a soft parcel of spare insulation he's left lying around. Two or three more box files fall into my lap, just to make sure the job is done properly.

The boss – who has obviously heard the commotion on his timely arrival – puffs upstairs to find me half-supine, winded, bruised, covered in strewn paperwork and scrabbling one-handed for my dislodged glasses.

"Ah, Mr Abley. Yes. Jolly good." He gently takes Mr Abley's file from my hand, then helps me up. "As per your recent reminder, I think it may be time we review our storage arrangements."