I received a letter in the mail, which was strange because nobody knows my address. I took the envelope inside, protected my body by donning a gas mask and gloves, and sliced the fucker open.

It was a ransom note, neatly typed on high-quality acid-free paper. The texture was so rich I was tempted to remove my gloves and caress it with my bare skin, but immediately recognizing the trap, I resisted the dangerous urge.

I read the message aloud and my voice was muffled by the gas mask. “Dear Larry. Deliver the Hammer of Vuvun or I’ll steal the kilogram, sending your precious metric system into chaos.”

I didn’t have any Hammer of Vuvun, so this letter was barking up the wrong tree. But I buy my supplements and laboratory chemicals by the kilogram, plus all my analog scales and measuring equipment deal in metric, so I couldn’t have this lunatic throwing that system into disarray (I only use analog because it’s harder to hack).

I checked my trusty 1987 encyclopedia to confirm that the precise weight measurement of a kilogram is defined by a physical object, the International Prototype Kilogram, which (according to the encyclopedia) is a little metal weight stored at the International Bureau of Weights and Measurements in France. I immediately called their director.

“Somebody’s planning to steal the kilogram unless I deliver the Hammer of Vuvun.”

“I’m sorry, who is this?” the director asked.

“There’s no time for that,” I explained. “You have to step up your security pronto or we won’t know what anything weighs anymore.”

“Sir, the kilogram was officially defined mathematically in reference to the Planck constant in 2018. So it’s a concept now.”

“Measuring weight with a concept?” I repeated incredulously. “How much does a concept weigh?”

“In this case, a kilogram. The point is that nobody can steal a concept.”

“But what if they could?” I asked.

“Well that would be…very bad,” the director admitted.

“Maybe we should change it back to the physical standard, to protect the Planck constant. We can physically guard a physical object, but ideas are under constant threat of sophistry, bias, hallucinations, and fallacious reasoning.”

The director scoffed. “I’ve been trying to get them to revert to the tangible Kilogram for years! They won’t listen. They’ve got their heads in the clouds, obsessed with pure rationality and abstract forms, while the little guy, you and me, we toil away here in the physical realm. You and me, we know what’s up, but the ivory-tower acolytes don’t trust the unwashed masses with tangible measurement standards.”

“Don’t be so defeatist,” I told him. “If we explain how vulnerable their ideas are in the post-truth era, they’re sure to see their error. We could convene an Assembly of Measurements and pitch our case there.”

“Nothing would make me happier,” the director said. “The Bureau’s shares plummeted when they switched the kilogram to a concept. But I’ve tried everything! Blackmail, seduction, reasoned arguments, murder, begging, but nothing works!”

“Just bring them this new information, and in the meantime, I’ll see if I can track down this Hammer of Vuvun. We’ll reconnect tomorrow and share our progress.”

“You got it. Talk to you tomorrow, Larry.”

I hung up the phone and grabbed a different volume of my trusty encyclopedia. I searched high and low but found no reference to any Hammer of Vuvun. Naturally I don’t have the Internet, because it can be hacked and somebody could trace me. So I added a green baseball hat and grey hooded sweater to my gas-mask-and-gloves, and replete in my disguise, I headed to a local Internet cafe. The Singaporean shopkeeper accepted my cash and I logged in anonymously. Then I searched for “Hammer of Vuvun” in my favorite search engine.

Various articles informed me that the Hammer of Vuvun was a rare piece of loot in a popular online video game where everybody is an adventurer and nobody is a peasant. It sounded suspicious to me, sounded like a scam, but I needed to get my hands on that hammer. The Singaporean shopkeeper accepted more of my money and I started playing the game, which was called Realm of Adventurers.

I’ve often speculated that real-life is itself a video game, or hologram, or simulation, so it felt very weird indeed to descend into this lower-level virtual world, like a virtual world within a virtual world. I only hoped that I would still be able to tell the difference when I emerged.

My first few hours in Realm of Adventurers were a gruelling spectacle of humiliation. The game’s tagline turned out to be untrue, as I was clearly a peasant among warriors. My strength and stamina were nil, I was frequently bested by seasoned virtual veterans, referred to as a noob (and worse), and sent on endless banal errands which often resulted in my demise. I asked everybody about the Hammer of Vuvun, but received only scorn. I also made a list of people who mocked me.

I played all through the night. By sunrise, I’d accumulated lots of loot and experience points (not to mention enemies), but still not a single clue about the Hammer of Vuvun. In my exhaustion, I was almost ready to accept the imperial system. But then, I chanced upon a wise old witch sharpening her broomstick on the outskirts of a village, and I asked her about the hammer.

The witch looked up and down the path. There was nobody else in sight. “Ask the shopkeeper,” she said through a little textbox.

“But we’re not in a shop,” I responded. We were out in the open virtual air, beside a creek which ran under a bridge.

“No, but you are,” she said. Then she cast a spell and disappeared.

How could she have known that I was in a shop? I looked around at the other gamers, peering at their screens, but nobody else was playing Realm of Adventurers. After removing my headset, I approached the Singaporean shopkeeper. He was reading a weathered hardcover tome and vaping. He smelled like cinnamon. I leaned over his desk and whispered, “I need the Hammer of Vuvun!” The gas mask added gravelly gravity to my voice.

He must have been expecting me, because he pulled a card from within the pages of his book and handed it to me. On the card, pre-written in pencil, were the words, “You kill rats in basement. I give you hammer!”

Another menial task! In Realm of Adventurers, I had finally evolved into a real adventurer, killing orcs in haunted castles and defeating whole teams of bandits. But back here in the so-called real world, I was demoted to slaying rodents in the cellars of shopkeepers. What’s worse, I had no real-life weapons except my wits.

“I have no weapon,” I told him.

The shopkeeper reached beneath the desk and pulled out a rusty, battered sword. Alongside the sword was another card, which said, “You use bastard sword!”

The sword was extremely heavy and dull. I hefted it over my shoulder and went into the dank basement. Rats were everywhere, scurrying around on the cement. I had no personal qualms with these rodents, but I needed that hammer. So, instead of killing them, I found a cardboard box and used my bastard sword to try herding them inside. But it was worse than herding cats. They shredded the cardboard with their filthy claws and teeth, then arranged the pieces into words on the floor which spelled, “The Metric System is Rubbish.”

Well, that was it. I smashed the little pests with my weapon, and I was glad the blade was dull. The metric system is the only thing that makes sense in this inexplicable world. The blade crushed their spines and skulls, splattered their brains and guts. They twitched in the dirt. Some fought back, trying to bite my legs, but my antimicrobial Kevlar long johns protected me. Finally, they were all slain and I went upstairs to claim my prize.

The shopkeeper handed me a USB drive and a card that said, “Thank you.”

I decided to test my bartering skills. “Is this it?”

The shopkeeper then handed me another card which said, “Well, I suppose you’ve earned a bigger reward.” Then he handed me two gold coins. I added them to my inventory and exited the Internet cafe.

Back home, I checked out the contents of the USB drive. I found a single file containing a 3D model of a beautiful blue warhammer. It had a ribbed grip on a short handle and a heavy head inscribed with writing in an alien character set. In my 3D rendering program, I scrutinized the prize from every angle. Zooming in, I found even more detail, more inexplicable writing. I zoomed in even closer and found the whole hammer was perforated with tunnels, and those tunnels were lined with houses, trees, and little people reading books or tilling their gardens. The Hammer of Vuvun was a world unto itself. The writing inscribed on its surface was too small for me to see from a distance, but too large for these tiny people to see from their minuscule vantage point. No wonder that the letter wanted this hammer so badly.

Still wearing my protective gas mask and gloves, I retrieved yesterday’s threatening letter and showed it the hammer on the screen. “I got you the hammer,” I told the letter. “Now what?”

But the letter didn’t respond, and I didn’t know who had sent it.

I decided to call the director to see how his progress had gone. But when I dialed his number, his secretary answered and informed me that she hadn’t seen him since yesterday. “To be honest, we’re pretty worried,” she said. “His wife hasn’t heard from him either. Should we call the police?”

“The police might be in their pocket,” I muttered. My mind was searching for answers.

“Whose pocket?” the secretary inquired. “Is the director in trouble?”

I ignored her questions. “Do me a quick favour. Measure out a litre of water and tell me how much it weighs.”

She quickly complied. “One kilogram,” was her answer.

“Then we still have time. Has the director received any mail since he went missing?”

“Why, yes. There’s a single unmarked envelope in his inbox.”

“Put on a gas mask and gloves,” I told her, “and rip that fucker open!”

Moments later, the secretary was breathing noisily through her own gas mask. Her muffled voice read the letter that she discovered within the envelope. “Dear Larry. I have your precious director. Meet me under the bridge in one hour, and bring the hammer!”

“Which bridge?” I asked.

“The letter doesn’t say,” the secretary answered.

I hung up the phone and put on some shoes. I was about to head out the door with the USB drive in my pocket, when I experienced an idea. “Maybe I should make a copy of the hammer,” I mused. So I plugged the drive back into my computer and started printing the hammer with my 3D printer. It took 55 minutes to print, but finally, the Hammer of Vuvun was physically manifested. I left it on my kitchen table, pocketed the USB drive, and ran out to the nearest bridge.

It was a walking bridge running over a shallow creek. I had to crouch to fit underneath. My corduroy pants got wet up to my knees. A gang of children wearing lab coats and gas masks awaited me there wielding microscopes and digital scales. The director was there, looking exactly as I had imagined him: kneeling down, blindfolded.

“I brought the hammer!” I told the kids, holding the USB drive aloft.

One of the kids operated a remote control cargo boat, which drove over the water. The boat carried another envelope, and I ripped the fucker open. A letter inside said, “Put the hammer in the boat.”

I wondered how much weight that little boat could carry. If the Hammer of Vuvun contained whole worlds within its perforated body, then it might be too heavy for the little boat. But that wasn’t my problem.

“Release the director!” I yelled at them. “And I’ll give you the hammer!”

One kid shoved the director. He stood up and bumped his head on the roof of the bridge, then bent over and started shuffling forward. I put the USB drive on the boat, and the remote-control operator made the vessel turn around and head back to the gang. But the boat was displacing more water now. Little waves sloshed over the little rails; the little motor struggled.

The boat sank just as the director stumbled into my arms. I tore off his blindfold. The kids were frantically typing a letter, but they had no way to deliver it to me.

“Let’s get out of here!” I told the director.

“But the hammer sank,” he protested. “They’ll still try to steal the kilogram.”

“Let them try,” I said, pulling him out from beneath the bridge, ushering him up the shallow bank. “We can’t live in constant fear of these terrorists. And after all, our scientific standards mean nothing if we don’t protect our relationships. We still displace water. We still weigh something, no matter what! If we have to fight to protect our ideas and standards, then we’ll fight! We won’t let them hold our directors hostage anymore!”

We reached the path and sunlight shone on the director’s face. “Maybe the kilogram lives inside all of us. Maybe we all are the kilogram.”

Then we went to the Internet cafe and played Realm of Adventurers.