Shatter was waiting for me. I knew she would be.

‘What is it you. Want?’ she said.

‘Eric’s got two legs. We could teach him to walk.’

‘Why would I. Ever. Help you?’

‘You wouldn’t be helping me. You’d be helping Eric.’

‘Why would I want. To help an over. Grown tea-making thing? Are you trying. To be nice to. Me because you’re scared. That I will bully. You because you nicked my. Mates?’

‘I didn’t nick your mates. They just helped because it was fun. It IS fun. If you helped me, I bet it would be fun.’

‘I’m not interested in. Fun,’ she said, and walked out.

A plane passed overhead so low that all the brambles in the doorway shook.

Then Shatter strode right back in. I thought she was going to tell me where the plane was going. Instead she scrambled up on to one of the fallen shelves – she really is good on her state-of-the-art foot – and started messing about with some kind of plastic box on the wall.

‘Shine your finger. On here.’

I pointed the finger torch at the box. She flipped it open. There was a row of switches inside.

‘Fuses,’ she said. ‘This one. Has tripped.’

She flicked the switch and BLAM!

A bomb of light exploded around us. Colours and shapes bounced around me. Dented paint tins, broken shelves, smashed floorboards, spiders’ webs and, most of all, Eric, lying on the ground like a giant angel.

Shatter had fixed the lights. They were so bright it made you feel as though everyone in the world could see you.

‘How did you know about that?’

‘When you were. All playing robots, I had a proper. Look around the place.’

She tugged a piece of string that was hanging down from the ceiling like a light pull and told me to stand back. When she pulled it, an entire table lowered itself down from the ceiling. Its legs popped out as it came into land. The table was made of metal with rulers engraved on its edges. We use our kitchen table for chopping veg and making pies. This one looked like it was meant for building jumbo jets.

‘This,’ I said, ‘is unusual. Why did they have a table in the ceiling?’

‘To save. Space,’ said Shatter. ‘That’s why they called. It the Space Age. Let’s. Start. Do you. Have a manual?’

‘A manual for Eric? No.’

‘Did you look for. One. Online?’

‘That’s the weird thing. I’ve spent ages looking at stuff about robots. I’ve never come across anything like Eric. There’s nothing about him on the whole internet.’

‘Maybe he’s from. The Future.’

‘Maybe he’s from space,’ I said, looking up at the legendary hole in the roof.

‘We. Are going to need a. Screwdriver.’

‘There’s one in my thumb,’ I said, snapping it back.

‘Let’s try these. Drawers too,’ said Shatter.

The hangar had big drawers on either side, crammed with nothing but screwdrivers – big, little, tiny, cross-top, flat-top, electrical, adjustable – every type of screwdriver you could imagine. Plus spanners and wrenches, pliers and wire cutters.

It turns out that Shatter really is a world-class expert on learning to walk. On her phone, she showed me clips of films the scientist Eadweard Muybridge made years ago. He took loads of photographs of animals and humans walking, and then made them into little films (which looked like flickery gifs) so that people could really study what was happening when a horse ran, or a boy walked.

Shatter explained that human beings learn to walk in stages. Such as crawling, bum shuffling, holding on to furniture.

‘We could take Eric through all those phases,’ I said, ‘but in a single morning.’

Neither of us really wanted to wake Eric to start with. It’s a strange thing, but Eric never looked more like a human being than he did when he was lying on the floor of that hangar asleep. We actually whispered in case we woke him, like you do with a baby.

Shatter spotted that his ankle bracelets were loose. ‘That’s why his feet. Are dragging. If he lifts them up. They just flop down. That’s never going to. Work. Give me a hand. Literally.’

‘You mean . . .’

‘Take your hand. Off and let me look inside. If we are. Going to make him. Walk, we. Need to know how. Muscles and tendons and nerves and everything work.’

I know it sounds weird. It’s not like I didn’t know there were circuits and chips inside Lefty. But seeing them sticking out all over the place made me feel unbalanced. When Shatter started poking around inside – not gonna lie – I felt queasy.

Shatter found this interesting. ‘You can feel. In your real. Arm when I touch your. Fake hand?’

‘It’s not a fake hand. It’s a real hand. It’s just not made of flesh.’

‘But you can. Feel it?’

‘No,’ I said. ‘I don’t have detachable nerve endings.’ It was true. I couldn’t feel any pain. But I was feeling something: confusion, maybe; embarrassment, a bit; but, most of all, I just wanted my hand back.

She picked up the screwdriver. I couldn’t help it. I screwed up my eyes as if I was waiting for an injection. She jabbed the screwdriver into Lefty’s thumb. I jumped. She laughed.

‘Can I have my hand back now?’

She tossed me back my hand. ‘It’s easy,’ she said. ‘Fingers are like. Puppets. They have. Strings. The. Strings all join. Up in the wrist. Pass me the soldering iron.”

We decided to make all the hardware adjustments while Eric was in sleep mode. The more awkward and complicated things seemed to be, the more useful Lefty’s integral tools turned out to be. I was learning as much about my new hand as I was about Eric.

Then it was time to wake him up.

‘OK, Eric,’ I said. ‘Let’s get you up on your feet so that you can walk out of here . . . Arise, Sir Eric.’

And Eric arose.

He placed his hands on either side of his body. He pushed himself up. Blue flames flowed down his arms and crackled over his joints.

‘Eric, are you OK?’ I said.

Every move he made flashed and sparked. He was a lightning storm with his legs. I backed away.

He was standing on his own two feet. He thrust his hand into the air and roared:

I AM SIR ERIC. AND NOW MY QUEST BEGINS!

He sounded pretty pleased with himself. He moved one leg towards me. Wobbled. Steadied himself. He looked like he was going to move the next one.

‘Whoa, steady,’ said Shatter. ‘Steady, Eric. Get used to standing. Up first. Keep it. Nice and slow.’

Straight away, the fire and lightning stopped. It seemed as though he was sucking all that energy back inside himself, trying to concentrate on keeping his balance.

I AM YOUR OBEDIENT SERVANT.

‘Sometimes, I think a word,’ I said, ‘can trigger his memory. Like when I said “armour”, he started to talk like a knight. Maybe if we just said, “Walk, Eric”, then just walking could be his quest.’

He stayed still, but tense like someone on the edge of a diving board, getting ready to take the plunge. Like he was considering his options. In my mind I seemed to see all the different ways there are of walking. Shatter swings her arms like a boxer swaggering into the ring. D’Arcy’s blades make her bounce slightly, like someone walking on the moon. Tyler walks with his head down, as though he’s looking for something. Everyone’s walk is different. I wondered what Eric’s walk would be like.

It was like an earthquake.

The floor groaned for mercy wherever he planted his massive feet. Chunks of the ceiling fell in his wake.

Shatter and I hurried after him, like when a mum or dad runs after a kid who has just learned to ride a bike. He kept going. He was way better than any of the robots you’ll ever see on YouTube.

Eric could actually definitely and completely walk.

It’s a pity that he used that skill by walking AWAY. But we’ll get to that later.

The point is we did it.

We taught Eric to walk.

‘He’s going. Out. Side,’ said Shatter.

It was true. Just like on the day he brought me here, he seemed to know where he was going, like he was looking for something.

I AM LOST.

Eric sounded more like a Marvel superhero announcing his name than a robot lost in an airport.

He stepped up towards where the broken door still lay on the floor. He put his foot on it. He lost his balance. He was going to fall.

I ran to him.

I grabbed his hand.

I held it tight.

With Lefty. Without me even thinking about it – without even trying – I had closed the fingers of my state-of-the-art hand around Eric’s fingers. Lefty had come to life. He was part of me at last. I was holding hands just like the toddler-me in the photograph.

That’s when I remembered.

Holding someone’s hand had triggered my memory, and in my mind, I saw . . .

You.