In the produce section of Trader Joe’s store in the Chelsea section of New York, Karl Holman holds an eight-foot-tall sign that reads “End of Line.” It’s six o’clock on a Tuesday, and Holman is managing the line for the second time this shift.

While customers test peaches for ripeness, Holman holds the towering metal pole aloft, making the banner’s orange and yellow lettering visible to anyone who gazes up from the shelves. For the next hour, the line’s end moved constantly.

Short and stout, with a salt-and-pepper goatee and a grey Trader Joe’s T-shirt, the forty-nine-year-old Holman addresses a knot of stopped customers who are blocking traffic. “Are you ready to check out?” he asks. “Step right here.” Customers glance at his sign and then file into place.

As the line forms in front of him, he takes tiny backwards steps to keep pace with its telescoping end. His moving target keeps him in motion, and he marks it with the dedicated poise of a Queen’s Guard at Buckingham Palace.

Starting by the tubs of cut pineapple, he inches deeper into the produce area, backing past the baby carrots and fresh herbs, past the clear bags of salad greens, and, while smiling and greeting passersby with a “Hi, how are you?” he hooks around a freestanding rack of fruit before stopping near the entrance. In a few minutes’ time he has traveled so far back that, without meaning to be metaphysical, he has transcended the proverbial end of the line and arrived at the beginning.

“Sometimes the line stretches all the way through produce,” Holman says, “up through frozen foods, and then back down frozen foods again.”

The system was pioneered at Trader Joe’s Union Square location, which was overwhelmed with foot traffic from the moment it opened in March of 2006. In the clogged aisles of the irresistibly affordable supermarket, heated confrontations erupted between customers over lack of elbow room and perceived incursions on territory. In the surging, irritable crowd, the end of the line was difficult to find.

“The way the system worked before, definitely didn’t work,” one supervisor said; she declined to speak on record for fear of upsetting TJ’s secretive parent company. “I mean, we knew it was going to be a good-sized store, but it was unlike anything the company had ever undertaken.” To accommodate foot traffic, they increased their fleet of registers from about ten to twenty-five. “And over time,” the supervisor said, “we designed the front-of-line, middle-of-line, end-of-line thing to create some order.”

Near a wall of fragrant bouquets, a man in a blue polo leans close to Holman. “Never seen it like this,” he says.

“Yeah,” Holman says in his supple, quiet voice. “It’s like this a lot.”

*   *   *

Cities function thanks as much to rules and signs as unspoken codes of conduct. People in crowds seek order and try to sort themselves in ways that reduce anxiety and increase safety and efficiency. Most of the time, they need help. When an employee stands among the masses directing traffic, there is little ambiguity and no one is going to get away with cutting in front of others. Then again, New Yorkers are famously cognizant of their surroundings.

Of all the world’s big cities, New York produces residents with a nearly panoramic consciousness and profound consideration of others: people who step to the side of bustling sidewalks to send texts or make calls, people who hold doors open for pedestrians behind them and move quickly so not to slow the passage of others. You can always tell the locals from the tourists. But groups of strangers often lack internal cohesion even when they share a common goal, such as getting groceries and checking out. Holman and others help bind crowds together and avoid what would otherwise become a mess of conflicting priorities, hazy boundaries and confusing expectations.

Holman has worked at Trader Joe’s for eighteen months at this point; before that, Dean & DeLuca and various restaurants. He caters private events on the side. Holman concedes that “End of Line” (or E.O.L., for those in the know) can be stressful work. Managing crowds this size every day sometimes wears on even the most patient individual, but he finds it deeply gratifying.

“If you want to get in line,” Holman tells a young woman in a white skirt and red high heels, “step right here.”

Keeping the pole perpendicular to the ground, he grips its center with both hands in a way that resembles a sage with a walking stick. He keeps a box cutter, X-Acto knife and pens inside a black canvas pouch on the back of his belt. He also wears comfortable work shoes.

Every end- and middle-of-line worker uses unique stock phrases and tones of voice. Some are gruff, some gentle. Some guide while others scold. One repeats, “This here is the back of the line. Back of the line, right here,” over and over like an auctioneer. Another heatedly addresses customers as “people”–“Hey, people!”–as if trying to alert them to some danger they are too dim to recognize.

Holman has a calming effect. Part of this stems from his voice. In place of a heavy New York accent or rough Brooklynese, the soft, musical lilt of his native Jamaica still colors his speech. His genial brown eyes seem to reassure people, as does his habit of offering help before customers even have to ask. Unlike the store’s hundred-year-old white Corinthian columns, Holman emits warmth and accessibility. It’s tempting to assume that his winning customer service springs from a broader personal philosophy. He has the Chinese sign for water tattooed on the back of his neck, a choice of body modification which suggests a worldview, an ethic, an approach to living. But it’s just a tattoo.

“I love water,” he says. “I love it.”

Facing the masses, Holman tells fretful customers to expect a wait of twelve minutes. It’s rush hour and packed with after-work shoppers. “Our regulars know not to come in between, like, four and eight,” Holman says. “They come in earlier or later.” Like other crew members, Holman estimates wait times by landmarks. When the line ends in frozen foods, the wait takes about fifteen minutes. When it ends by the entrance, the wait takes twelve minutes. Customers wait eight minutes from the vitamins, five minutes from the demonstration station, and three from the bread.

“It goes fast,” Holman tells a worried-looking businessman, who stares blankly at him as he passes. It’s challenging to differentiate customers whose brows are furrowed from searching for the line from customers straining to remember what other items they need to buy. And this isn’t even Trader Joe’s busiest New York store. Of the three in Manhattan, Union Square holds that title. The Upper West Side store comes in second, and Chelsea third.

The line’s exact end can get hazy, diffuse. In certain spots it frays, blending with the many people milling around endcaps and cold cases and hovering by the demonstration station eating free samples. On this day, the demo staff serves bowtie pasta smothered with Arrabbiata sauce. Free food induces a certain hysteria, and the increased frenzy further confuses the consumer swarm. Are these people standing here because they were shopping? Are they waiting to fill tiny paper cups with free coffee? Is this the register line? The direction and intent of traffic is often unclear.

“The longest wait I’ve ever seen,” a supervisor says, “is fifteen minutes.” But that isn’t the longest on record. A crew member named Teresa remembers lines so long during both Hurricane Sandy and Thanksgiving last year that they snaked through frozen foods in both directions and out onto the street. A desperation filled the air on those days, a fog of tense hysteria that seemed to waft from the throngs of customers who streamed in from the street. “The honor guard had to close the front door,” Teresa says. “We had to let the line go and let people in, let the line go and let people in. It was a process, but we’re efficient.”

*   *   *

Located on the ground floor of the historic Mattel Building at 6th Avenue and 21st Street, the Chelsea store fills half the space that a 35,000-square-foot Barnes & Noble occupied for fourteen years. When the bookstore closed in March 2008, the landlord sought a big-box retailer to fill the vacancy. Trader Joe’s opened on July 12, 2010, at 8:05 a.m. It would have opened at eight, but a Fox News crew slowed the process by filming the event. As with the 14th Street location, enthusiastic customers lined up outside the morning before opening. Staff high-fived shoppers as they entered and handed them free cookies. The lines were manageable.

Trader Joe’s fans are the kind who start Trader Joe’s missed connection tumblrs and grieve online about discontinued items such as Triple Ginger Lemon Ice Cream (discontinued on 4/4/2013) and Highbrow Chocolate Chip Cookies (spring 2013). They’re the kind of fans who fill suitcases with products to take home to TJ’s-free states like Hawaii and South Dakota; the kind that, like college music professor Bruce Roter of Albany, N.Y., conduct years-long letter-writing campaigns to convince the chain to build stores in their neighborhood. (In Roter’s case, the chain eventually did.)

In addition to an end of line, staff fills a middle of line, or M.O.L., position. Like its kin, middle of line carries a sign and informs customers how to reach the line’s end; when the crowd thins, M.O.L.s often set down their sign and return to performing other tasks, such as stocking yogurt and collecting shopping carts. Closer to the exit stands the F.O.L., or front of line; they direct customers to cashiers. Of the store’s thirty registers, nearly every one is constantly in use.

The store normally keeps staff on register for two hours per day, but crew members work on a revolving, hourly system, performing different duties throughout their shift: helms person, demo station, maintenance, first end assistance, stocking. The changing of the guard happens at the top of every hour with the ring of a bell.

From the registers, customers lug heavy paper bags toward the front door. They have successfully completed a grocery store sortie, yet their faces show little sign of pleasure in the accomplishment. Some scowl. Some frown. Some stare distantly. All cut through a swift stream of customers moving both in and out of the front door, a continuation of the pedestrian traffic on Manhattan’s streets.

On the side of the entryway opposite the registers, a young couple steps in from Sixth Avenue and stops in produce. Stunned, he scanned the line, mouth open. “Is this going all around the store?” he said.

Holman stands smiling nearby. “Yes,” he says.

The man looks ready to bolt. His girlfriend tucks her red hair behind her ear and reassures him. “Maybe it will get smaller as we go around the store,” she says. Her positive attitude is enviable and effective. With that, her boyfriend shrugs and grabs a shopping basket, and they weave through the crowd toward frozen foods.

“At end of line,” Holman explains, “you’re the help desk. People come to you with questions. ‘Where is so and so?’ ‘Where is the bread?’ ‘How long is the wait?’ People ask that a lot.” If E.O.L. were a spiritual retreat, Holman’s great lesson would be patience. “And a friendly demeanor,” he says. “A real friendly demeanor.”

While the young couple shops, Holman begins inching forward. In a fortunate turn of events, the line is shrinking, and he takes incremental steps frontward that carry him out of produce and into the aisle containing nuts and pet food. Beside boxes of something called Double Wide Cat Scratcher, he holds the sign overhead and directs traffic. “Are you ready to check out? You can step right here.”

As Holman stands by a cereal display, crew members wheel dollies full of boxes through the crowd. Foghat’s “Slow Ride” plays overhead.

In the time it takes one couple to decide whether they want the ciabatta loaf or the rosemary parmesan rolls, the line has returned to its previous length, stretching back past the demo station and dissipating by the “6th Ave Dairy” case.

There, people mill around, pushing carts in directions that block passage and increase confusion. Ready to check out, they don’t know how to start, so they stand there and draw other people in a clot.

Nearby at a narrow endcap, a dark-skinned young clerk sets a box of Sesame Snacks on the floor. Hunched over, he tosses crinkly bags on the low shelf, his torso hanging like a deflated balloon. Without warning, he stands straight up and faces the crowd. “We have two lines, people! Two lines!” He sounds angry. Customers recognize it. Yet nobody moves—not in a substantial way. The man shrugs, and in a heavy New Jersey-type accent says, “Whateva’,” and empties the box.

Having retreated up the vitamin aisle, Holman falls back into produce before breaking for lunch at seven p.m. Outside the store, a street vendor sells sunglasses, wallets and protective cell phone sleeves from a fold-up table. Pedestrians stream past him, along with bicyclists and cabbies. He has a lot of merchandise but no line.

A man with greying shoulder-length hair walks toward Trader Joe’s. He tells his wife, “Let’s see how long the line is.” Then he opens the door and they walk in together.

*   *   *

Aaron Gilbreath has written for Harper’s, The New York Times, Paris Review, Kenyon Review, Oxford American, The Believer, The Morning News, The Threepenny Review and Virginia Quarterly Review, and wrote the musical appendix for The Oxford Companion to Sweets. Follow him on Twitter

Marc Pearson is a cartoonist from Melbourne, Australia. He is currently running a one-cat hotel.