There is too much blue. Too much blue, and too much green, and Nev finds a fresh breeze brushing past his face. The breeze isn’t supposed to be there. It’s been raining non-stop for weeks, and Nev isn’t used to the blue. He’s also not used to the sight in front of him: he’s supposed to be looking at the new concrete fixture holding up the enormous, quartz Bendigo Rock.

Instead, Nev is looking at the enormous, quartz, missing rock.

Nev calls the police.

The officer is also too blue, and he doesn’t seem to share Nev’s distress. He flips open his notebook, pen poised, and says drily: ‘so, they took a rock.’

‘Yes,’ says Nev. ‘Quite a large one.’ They’re in the National Rock Garden, so rocks are in plentiful supply (though slightly less so than before). But the Bendigo Rock, pride of the garden’s rock display, layers of quartz and a small amount of gold, is missing, presumed gone forever.

‘Was it a valuable rock?’ says the policeman.

Nev can’t help it. ‘I guess you could say its value is purely sedimental.’

There’s a beat. The officer doesn’t laugh. ‘Was it valuable?’

Fine. ‘Not really,’ Nev says. ‘It’s got maybe $200 worth of gold through it. It would have cost more to hire the crane.’

The scribbling stops momentarily. ‘What makes you think there was a crane?’

Nev feels the full weight of suspicion on his shoulders. Strangely, it feels heavier than the Bendigo Rock. ‘Have you seen this rock?’ Nev asks. There’s another pause and he assumes, correctly, that the officer hasn’t. ‘It’s big.’

‘Can you think of anyone who would want to steal the rock?’

He thinks for a moment. ‘It isn’t a food... so it can’t have been Nando’s.’

In fairness, there’s probably a reason that the police officer isn’t taking him seriously. When he leaves, promising he’ll let Nev know if he hears anything, Nev wonders if he maybe should have mentioned that the rock was an important piece of history. Neglecting that information makes him feel a bit guilty.

To ease that guilt he decides to put on his investigator’s hat. He’ll find the rock himself.

It must have been easy to lift the rock from its concrete fixture: the concrete was still wet last time Nev looked, thanks to the weeks of rain. He surveys the surroundings and sees tiny particles of it; crumbled bits of concrete are scattered at the base of the rock display. Nev can see them leaving a trail towards the edge of the rock garden. So he follows them out onto the street, along the path, around some roundabouts, and tracks them all the way through the National Arboretum, past some suspiciously crushed plants in the rose garden, to Lake Burley Griffin.

There is too much grey. The concrete shores of the city’s centrepiece are grey; the sky is grey, now, and the strange structure Nev has found himself standing next to is grey. He’s not sure what it is—he’s never seen something like it before—and he’s certainly not sure why it is moving. But is it moving? It looks more like breathing. Nev peers more closely at it, and he wonders how he could have gotten so close without working out what it is. Nev is looking at an enormous—

Concrete monster.  ‘Concrete,’ Nev says, shocked. ‘Concrete monster.’

But that’s the thing about accidentally chasing an inexplicable concrete monster across a concrete surface: they’re really hard to see.

It tries to run, and Nev finds out the other thing. They’re really slow.

The problem is what to do with it once he has it cornered.

Nev thought the Skywhale was the most ridiculous thing he’d ever seen, but it wasn’t even close to the thing he’s looking at now. It’s tall, and grey, with clumsy bouldery shoulders and rocky-looking legs.

He blinks up at the monster. Somehow, the monster blinks back at him. It makes a gravelly kind of growl, and Nev thinks maybe it’s his cue to leave. Except how can he leave, when this thing is holding the Bendigo Rock? The monster growls again.

Because while Nev is having a crisis in the form of an enormous monster, so is the monster. I’m not concrete, the monster thinks. It can’t articulate this thought because, though sentient, it’s still a rock-like thing. I have no concrete.

Nev doesn’t know that. He hasn’t ever googled the difference. It’s not on the surface: it’s in the particles. To make concrete, coarse gravel and rocks are added to cement—the binding substance made from calcium and silicates and oxides. Mixed together, they form something like rock. This monster is moveable, malleable, fluid-in-a-rocky-kind-of-way. It’s cement, and only cement. So when Nev calls it concrete, the monster remembers what it is missing. It knows there’s no reasoning with Nev. His words hurt, but Nev isn’t worried about feelings: he’s worried about the Bendigo Rock.

‘Please don’t hurt the rock,’ Nev says.

The monster growls. It doesn’t care about the rock. It’s stuck to the rock. But it can feel that hold loosening. The monster never dried, which is why it can move. And that’s why it is falling to pieces.

It starts to rain again, then, fat drops splatting on to Nev’s head. He sees a drop hit the monster, and another, and another. It starts to pour. Parts begin to fall away, and Nev begins to have a thought. Water is that thought. It’s just a drop of a thought, a trickle on the way to a bigger idea.

See, the thing about a cement monster is that it needs something around it, through it, to hold it together. It needs the concrete to survive. This monster doesn’t have that. It was never meant to move at all. And so it begins to crumble.

Nev still doesn’t know the difference. But he knows how to destroy the creature—and how to get his rock back. He has to push it into Lake Burley Griffin.

Which he does.

The cement monster blinks up at him as it sinks below the surface of the water. I’m melting, it thinks, and Nev almost thinks the same thing. He looks down at it—and his Bendigo Rock—and feels something like remorse.

Maybe I’m the monster, he thinks.

He phones the police.

‘I know where the Bendigo Rock is,’ he says, and wonders if he should even bother explaining how it got there.

Kelly Williamson is not an authority on the National Rock Garden or Canberra, but she did Google cement and concrete. She’s not convinced she knows the difference. You can find her on Twitter @keds_w, where she is still confused.