“Take cover!” Lara yelled, pulling the nearest box she could find into position, forming a makeshift barricade.

Dina and I followed her example, dragging more boxes across the floor, placing them around us in a rough circle, stacking one on top of the other so that quickly we had created a cardboard fort. We crouched in the narrow space at the centre as the drones buzzed our position, their grappling hooks thumping against the cardboard ramparts. We had bought ourselves some time, but it wouldn’t take long for the machines to penetrate the paper-thin defences.

“We can’t just sit here and wait,” I said. “We have to find a way past them.”

“I could call up some more rats,” said Lara.

Rats were resourceful but no good to us right now. “They’re no match for those drones.”

I stuck my head above the cardboard parapet for a better view of our attackers. There was a harsh whirring noise and my eyes were dazzled by the flash of a barcode laser as the nearest drone instantly detected me and abruptly altered its flight path. I ducked down, but not quickly enough. The drone struck.

It was only on me for a second before Dina batted it away with a hand blender. But in that time half my head had been viciously covered in garish wrapping paper decorated with fluffy bunnies wishing a “Hoppy Birthday” and fixed in place with half a dozen bits of sticky tape.

“Hunter-Wrappers,” I said, observing the drones. “They scour the warehouse for open orders and aggressively wrap them.”

I tore off the paper, wincing as the sticky tape clung to my hair. We were pinned down, unable to do any good here. Making a decision, I climbed out of the cardboard fort.

“Come and get me!” I called to the circling drones.

They hesitated. Perhaps my unpredictable behaviour had confused their logically minded processors. If so, it didn’t slow them down for long.

The first drone broke formation and came whistling towards me.

I unhooked my backpack and unzipped the top compartment. Dad had made a lot of unwise purchases from Rocketship.com. He’d been carried away by their tempting sales and competitive pricing, but never more than during their camping promotions. Dad loved camping and hated it too. It was an odd relationship. He was always searching for the perfect tent – and in the Freedom Family Vista Pop-Up 500 he believed that he had found it, at last.

I whipped the tent from the backpack. In pre-erected form it was a small circle of folded material just a few centimetres thick.

I could feel the drone’s laser-eye picking out a point on my forehead, like a sniper finding his target. Its sticky-tape dispenser rippled as it prepared to attack.

I unleashed the Freedom Family Vista Pop-Up 500.

Wafer-thin super-strong carbon-fibre struts pinged into place, turning the flat disc into a family-sized habitation in exactly zero point seven seconds.

The fast-moving drone smacked into the sheer nylon cliff face, snapping two of its delicate rotor blades and bouncing off the taut material at an angle that caused it to stall. Unable to maintain height, it dropped to the floor where, sadly, it didn’t explode in a blazing fireball of doom, but judging by the crack in its casing and the way it just lay there, it wouldn’t cause us any more trouble.

One down, two to go.

Unfortunately, I was all out of pop-up tents. The remaining drones regrouped, their rotors buzzing angrily.

“Luke – let’s roll!”

While I’d been dealing with the drone, Lara had noticed that a couple of the boxes we’d used to build our fort could be useful in another way. They contained transport – two bright-pink scooters. Lara pushed one along the floor to me. I caught it and jumped on the deck. As my hand gripped the handlebars I realised that one of them was a throttle. The scooter was electric – and charged.

Lara zipped past me, Dina standing on the deck behind her holding on to her waist. “Punch it!”

I twisted the grip, the tiny scooter tyres squeaked against the polished floor, the back end fishtailed and I flew after them. We slalomed around boxes and darted past shelves. The lumbering robots spun on their tracks and tried to swat us with their extendable arms, but we wriggled past them.

“They’re still on us,” said Dina. From her position behind Lara she had a good view back down the aisle.

“Split up!” I shouted across the aisle to the girls.

Lara nodded and at the next gap in the shelves she peeled off down one side. The drones did likewise – now we each had one on our tail.

I hunched over the handlebars and turned the throttle to maximum, gunning the brushless motor. I sped down the narrow aisle, the gadgets shelved on either side of me passing in a blur.

Up ahead I could see the far side of the storage unit and the door into the next one.

But just when I thought I was going to make it, the scooter’s electric motor gave out. The scooter trundled to a stop. Desperately I resorted to old-fashioned trainer-power, kicking off the floor and keeping it moving that way. But it was futile. I discarded my ride and as it clattered to the floor I turned to face my pursuer.

I could see Lara and Dina hotfooting it down the aisle towards me, having also ditched their scooter. Behind them loomed the second drone, closing fast.

“C’mon, Luke,” I muttered to myself. “Think of something. Qu—”

I didn’t manage to finish the thought before, high up on the shelf next to me, I glimpsed a blur of movement. A figure leapt out from between a table-top dishwasher and a portable humidifier.

A figure in black.

Lara had seen him too. “Is that—”

“Serge,” I confirmed with some surprise.

With a rustle of silk pyjamas he sprang from the shelf, landing lightly on the floor. Plimsolls whispering on the polished surface, he slid between us and the approaching drones. Then, in one fluid motion, he flipped open his messenger pouch and dipped both hands in. When they re-emerged, each held a paper aeroplane. Drawing them back Serge launched the planes with a synchronised throw.

The paper aeroplanes were tightly folded, the throw perfectly weighted. Somehow, whether by instinct or calculation, Serge had accounted for the cross currents of air, humidity, even the magnetic spin of the Earth. The planes flew unerringly towards their targets, like ninja throwing-stars but more paper-y, simultaneously striking the drones at precisely the same point on each. It was a small open port – perhaps for a charging cable – on the lower front half of the casing. The effect was instantaneous. A muffled bang came from deep within each drone, followed by an acrid burning smell. The drones lost power, their rotors stuttered. Black smoke poured from their casings as they tipped unstoppably towards the floor. If there had been a pilot on board, this would be the moment when he sent out a Mayday call.

The drones crashed down, bounced once and skidded either side of the black-clad Serge, before coming to rest in two gently smoking heaps.

Only then did Serge turn around.

Dina whooped and Lara was open-mouthed with amazement. “They didn’t teach you that at the leisure centre on Moorside Road.”

Serge padded past us, heading to the next storage unit. “Now, shall we prevent the end of the world?”