I ask Tumi. But it's just a play for time. I've found what I've been looking for. I close my hand over a broken brick, stand up and hurl it with full force, not at his head, but his hand. Tumi howls and drops the screwdriver. It plinks into the water and disappears, the current sweeping it away with the other detritus. Busi shrieks in dismay.
Tumi scrambles out of the water and lunges for me. But it's Sloth's arm he grabs, tearing him out of the sling and swinging him out over the canal. Sloth drops into the water, too surprised to make a sound.
"Now what?" Tumi leers. He doesn't see Sloth resurface or start paddling for the bank, his long arms stroking elegantly through the water. But he's losing against the current, the angle of his trajectory towards the shore getting sharper as it tugs him away.
"Fuck you," I say and stab him in the side of his neck with the broken porcupine quill. I clutch onto my bag and plunge into the canal after Sloth without sticking around to see the results.
We wash up kilometres away, clinging to each other, battered from being hurled against the cement walls all the way down, with various additional minor wounds, including scratched arms and legs from a surprise collision with a broken branch wedged under the water.
It takes a long time to find the strength to stand up and carry on, and when I shrug Sloth onto my shoulders, he is so waterlogged, it feels like he's put on ten kilos. Sloth is ominously quiet. It's an indication of how much shit we're in because normally he's the first to complain, bleating rebukes in my ear.
The worst is that I don't know where we are. It's not like I'm the world authority on Joburg's storm drains, but I've been down here enough times looking for lost things to know the basic lie of the land. This is all unfamiliar. The tunnels are a scramble of pitch-black termite holes, some of them narrowing away to nothing, like whoever was digging them got bored and wandered off. The original gold diggings maybe, when Johannesburg was still just a bunch of hairy prospectors scrabbling in the dirt. Maybe we'll bring home a nugget the size of Sloth's head.
Sloth guides me through the dark, squeezing my shoulders like handlebars. If we could just find a lost thing, I could follow the connection back home, like a trail of breadcrumbs.
But hours later, we have not stumbled on anything, not a lost thing, not an exit, not even a passage that leads anywhere, just one dead end after another in the humid dark. Sloth squeaks once, a bleak little noise as I slump down against the wall. My feet are aching, my stomach is clenched, like hunger is a sweet it could suck on.
"Don't sweat it, buddy. We'll get out of here," I say. "No worries."
But he can tell I don't believe myself. It's so black down here, my eyes invent ghosts to make up for the sensory deprivation, ripples of black on black. It's as quiet as purgatory.
And then Sloth chirrups and looks up with a sharp jerk of his head. Swimming is not the only thing he does better than me. I strain to listen. My heart drops into my gut. "Is it them?"
There is a low rumbling sound, almost indiscernible, but it's building, like house music rising to a dancefloor crescendo. I stand up in a hurry. "Water?" There are reports every year of kids who have drowned in the drains, caught out by flash floods that come out of practically nowhere while they're messing around in the tunnels smoking dope or looking for ninja turtles.
But Sloth clucks in irritation, shutting me up so he can listen. It's something else. He bats at my face with urgent pawings, the way he does when I've overslept. "All right, all right," I say, staggering to my feet and in the direction he guides me, towards the epicentre of the noise. It better not be a wall of water.
The sound reverberates through the tunnels, ramping up to a teeth-rattling earthquake. There is a glow up ahead, as if of civilisation. Hope sparks in my gut. I stumble forward, round a corner, into blinding artificial light. I make out huge metal ribs lining the tunnel like the belly of a robot whale. And then a whip of glass and metal thunders past inches from my face.
The blur of