We’re racing through the streets, leaping over people slumped on sidewalks and spilling from cars, and all I can think is I can’t remember where we’re going when I slam into Neven. He’s stopped dead and I’m about to scream RUN! when he whispers, “It ricochets.”

My belly tightens in a tourniquet of dread. That’s what they all say. Right before the fugitive bio-nanites, lab escapees hiding out in all our brains, go berserk. Oops, the researchers had said. We didn’t foresee the whole airborne thing. The lung-transference thing. The brain-breach thing. Sorry about that.

“Neven!” His gaze is vacant. Preoccupied.

He collapses.

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“No!” I shake him wildly. We’d held out for so long. Why now? He’s staring up at a print taped inside the window of a store: Escher’s iconic drawing of hands drawing themselves. My mind cramps. Hands drawing themselves drawing hands drawing themselves drawing hands —

ricochet

The thought rebounds inside my mind, faster and faster, scything through my memories. I clutch my head. I need to go … somewhere. Do … something. I hug Neven. “Please wake up. You said you’d never forget me. That you forgive me.” Because the ricochet, it’s —

All my fault.

Inexplicably, my memories flood back. I swallow. After the infestation, while governments scrambled, while the world held its collective breath, I’d reasoned the nanites were, fundamentally, computers, and did what any self-respecting programmer would do.

I wrote an app for that.

Oh my God.

I race towards my apartment, because that’s where we were heading. That’s where I can fix it. Fix Neven.

Oh Lord. What did you do? I’d only wanted to find my soulmate, that’s all. So I wrote a dating app. Used myself as a beta tester. Hacked the nanites and instructed them to find my perfect match. Neven. But to fulfil that directive, they evaluated everyone. Signed up everyone. Networked everyone. And spread the ricochet.

Anguish pours into my blood, and I stumble. Don’t leave him. Go back. GO BACK. I shriek and collapse, every muscle a knot of agony. Dear God, WHAT IS THIS? But I know.

My app exploited the bio-nanites’ access to love’s secret sauce: chemistry. Biochemistry. Hormones, pheromones, neurotransmitters; the nanites not only matched couples who were compatible, they were biochemically compatible. Relationships shattered as old married couples and newlyweds alike abandoned their current partners for their perfect match. That’s why the streets were so clogged. They were frantic to be with their newfound loves. Because the nanites forced everyone into a state of biochemical withdrawal until they were.

The state I’m in now.

My withdrawal fades as I rush back to Neven. I kiss him desperately, then gasp as his arms encircle me, sleeping beauty awakened. “RUN, GODDAMMIT!” I yell, and he does.

We burst into my apartment; who needs locks when everyone’s a vegetable? Come to think of it, why are you the last ones standing? I wish I knew.

The holographic blocks of code I left up, they’re utterly foreign. Dear Jesus, I can’t remember how to program —

“It ricochets.”

Neven. My heart freezes. I find him in the bathroom, staring into the side panel of the trifold mirror reflecting his reflection reflecting his reflection —

ricochet

It’s never-ending, like hands drawing themselves drawing hands —

ricochet

ricochet

It’s also familiar. Why? I squeeze my temples as Escher’s hands loop, as the mirrors recurse through my mind — wait. Recursion. That’s why it’s familiar. It’s like that — thing I do on computers. Coding. Sometimes I’d inadvertently write a program that called itself, looped over and over, recursed into infinity-y-y —

ricochet

ricochet

ricochet-t-t-t

But most systems have built-in programs to limit recursion. Otherwise the code continuously executes itself until the system runs out of memory.

I freeze.

Runs out of memory.

As in the ricochet effect.

The nanites. They’re computers without recursion limits. The moment someone thinks of recursion, the nanites use up the brain’s resources to follow that recursion into infinity-y-y-y—

ricochet

And my networked app allows the recursion to spread.

Oh, God. It’s hopeless. I have to think of recursion to fix the ricochet-t-t-t —

ricochet

ricochet-t-t

I squeeze my eyes closed as my heart pounds, my mind on the abyss of the ricochet-t-t-t-t-t-t-t-t-t —

But you held out, dammit. Why?

Don’t know — little computers — in my head — eating my memory —

ricochet-t-t-t-t-t-t-t-ttttttttttttt

No use — everyone succumbs — a world of sleeping beauties —

Sleeping beauty awakened.

My eyes snap open.

Neven woke — when I kissed him. Why?

ricochet-t-t-t-t-t-t-t-tttttttttttttttttt

My memories came back — when I hugged him. Why?

ricochet-t-t-t-t-t

Because love — it’s like —

A drug.

Biochemicals.

I hold Neven close, kiss him tenderly, and the ricochet recedes. Those butterflies I feel, they’re really oxytocin, dopamine, serotonin. The biochemicals of love. Maybe they drug the bio-nanites. Slow the recursion. Free up memory. Am I the last one standing because I was the beta tester? The first one to reach my biochemical soulmate, to pump out love’s biochemicals? Maybe the nanites learnt from me. Tried to force soulmates together to … produce enough biochemicals to medicate themselves out of the recursion.

Maybe I can drug the nanites by thinking of Neven.

I flick the holographic display and frantically start coding —

ricochet

I love you. That’s what Neven said when we first heard about — the bad memory thing. I’ll never forget you. My fingers fly over the interface. C’mon, c’mon —

ricochet-t-t-ttttttttttt

But he did forget me and so did I because who is this man? If only I could remember his name — rhymes with seven heaven nevennnnnnnnnn-n-n-n-n-n

Oh, God, upload —

ricochet

RICOCHET-T-T-T-T-T-T-T

RICOCHET-T-T-T-T-T-T-T-T-TTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT

————

———

——

—

I open my eyes.

Neven. He’s smiling. “I told you I’d never forget you.”

Love’s biochemicals flood my brain, and I swear I hear the nanites sigh.