Lenny fell in love with Bea around burrito number five. He recognized that dizzying jolt to his brain the instant the tunnel’s mouth sighed with a sweet pneumatic hiss and the vacuum-sealed burrito glided in.

Three hours and twenty-one minutes earlier, 2,553 miles away, at her end of the tunnel in the East Bay facility, Bea had been thinking of him. She must have. He wished he could trace her regard for his existence beyond the minute or two it would’ve taken her to pluck the flash-chilled burrito from the sorting dock, nest it in its carbon-fibre pod, and send it in the near-vacuum of the tunnel deep into the Earth to be blasted across the continent at just below the speed of sound.

Lenny worked the subterranean off-ramp in New Jersey, where multitudes of the famed Mission burritos of the Bay Area arrived levitating on magnetic currents, ready for dispatch to the ravenous gullets of the five boroughs of New York City. Since the blast aboveground, the flow had dwindled to one burrito at a time. Lenny stared at each with longing, wondering if Bea had tucked a note for him into the Mylar pocket.

When her first message arrived, the eerie rumble still vibrated through the basement walls. Lenny was pacing in circles, running through scenarios — alien invasion, given the contact the year before; nuclear war, given … many things — and going mad at the thought of dying underground, alone. He was ready to venture out and face the radiation or the new overlords when the first burrito slid out with a note attached to it. Here: an end-of-the-world burrito. Best you’ve ever had.

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Apparently Bea had never expected her message to reach anyone. Who knew insomnia would drive them both to work before clock-in time, saving them? Now she was sitting on a dragon’s hoard of burritos, that morning’s shipment enough to feed them both for weeks. They could stay put, wait for things to blow over.

The problem wasn’t food — or the aliens, or the bombs. It was, as usual with Lenny, love.

Around burrito number nine, he wrote on a whim, Folks might get the wrong impression if they saw you spoiling me. He slipped his note into a Mylar pouch, which he placed inside an empty burrito pod and sent down the tube.

Bea volleyed back, Yeah, they’ll think you’re my grandson. PS What folks, Lenny???

He chewed through the cold tortilla. Was she flirting back? Or letting him down gently by hinting at her age? Which wouldn’t be an issue.

Lenny agonized over his retort for hours, maybe even days. Afterwards, every exchange between him and Bea felt loaded with subtext. Chorizo with Mexican red rice, refried pinto beans and real Monterey Jack, Bea wrote. Enjoy :) Was a smiley face coy or merely friendly? What about one with a wink?

Lenny talked to her in his head, Bea nodding, her dark eyes dancing. But whenever he put pen to paper, his lucidity evaporated, crumbling to the overeager babble of a hapless nitwit.

At one point, Bea wrote, A day is a long time.

He stared at the plastic sleeve, yearning to sweep her into his arms. He placed his hands where her own had been three hours and twenty-one minutes earlier.

Are you bored, too? Lenny replied. I thought we could pass the time by getting to know each other. He proceeded to tell her about his favourite music and where he’d grown up, including several major formative events from his childhood.

After what felt like eternity, Bea wrote back. It was an ingredient list. Carne asada, sautéed mushrooms and salsa verde.

No smiley face. Lenny’s heart broke.

What’s happening, Bea? What’d I do? he wrote.

Several torturous hours passed. Then: Imagine a map of an island, alright? It’s the most high-fidelity, super-detailed map of the place there is. Now imagine the map itself is on the island. You see what that means? There must be a map of the map inside the map. And inside that second map — another one. On and on. It’s maps all the way down, Lenny.

Lenny had heard a paradox like this somewhere before. But Bea seemed to be opening up at last. Her scrawls looked frantic, streaking across the margins like startled flamingos. He turned the riddle around and around, then wrote back, What about the map maker? Is he also in all of the maps drawing them … and himself?