Jermaine Crawford was too young to understand. When he joined the cast of The Wire as a teenager, the now 24-year-old actor told me, "I had absolutely no idea what I was a part of." He began to make sense of his role in the show that he’d been dropped into only when writer-producer Ed Burns gave him a pep talk. That day, the cast and crew were shooting a scene for the show’s fourth season in an old Baltimore elementary school. Crawford, who stars as poverty-stricken eighth-grader Duquan "Dukie" Weems, was surrounded by local kids playing students.

"Take a good look around you," Crawford remembers Burns telling him. "A lot of these kids in this classroom are real-life Dukies, and you’re telling their stories." It quickly dawned on the then-14-year-old Crawford what he was doing. The program is technically fiction, he said, "but it told the damn truth."

Fifteen years after creator David Simon’s opus premiered on HBO on June 2, 2002, it remains an unmatched portrayal of the inner workings of an American city in decline. The Wire slices deeply into Baltimore’s decaying public institutions. "It is perhaps the only storytelling on television," Simon told The New Yorker a decade ago, "that overtly suggests that our political and economic and social constructs are no longer viable, that our leadership has failed us relentlessly, and that no, we are not going to be all right." Through the eyes of a diverse ensemble of police officers, drug dealers, politicians, and citizens, the audience sees how these failures affect a majority African American community. The series infamously never won an Emmy, but now it’s being used as a teaching tool in classrooms across the country.

That the show proved to be both wise and prophetic is of no comfort to Burns. "It’s only aged well because the world has actually gotten worse than what we created with The Wire," said Burns, a former Baltimore detective who became Simon’s writing partner. For Burns to arrive at that point, we didn’t even have to talk about the death of Freddie Gray, Attorney General Jeff Sessions’ recent memo imploring federal prosecutors to once again seek the harshest possible penalties for nonviolent drug offenders, or a health care bill backed by President Trump that would leave 23 million more people uninsured.

Police brutality, the misguided drug war, and policies that prey on the poor — these things haven’t disappeared since The Wire wrapped after five seasons in 2008. "It still resonates," said the 70-year-old Burns, who these days lives in rural West Virginia. He’s proud to have helped shape the landmark program, but has no interest in rewatching it. There’s no need. "I don’t go back," Burns said. "I know that world intimately. To me it’s just a tragedy. I don’t have to see it. I sort of lived it." (Simon has long viewed The Wire as a Greek tragedy.)

The show is full of characters who, with few other options, have traveled down self-destructive paths. The audience doesn’t often get to see all the factors — internal and external — that have led them astray. But in the fourth season, we’re introduced to four black adolescents whose futures are uncertain. The arc unfolds over a semester at a junior high. It’s painfully affecting. "You’re seeing the lives of kids at stake," Burns said, "and that’s powerful drama." The Wire was never better than when it was telling their stories.

Burns was particularly equipped to examine an inner-city public education system. After spending two decades as a cop and then cowriting the book The Corner: A Year in the Life of an Inner-City Neighborhood with Simon, in the ’90s he became a geography teacher at Baltimore’s Hamilton Middle School.

"I had been a cop for 20 years, and I had been in ’Nam for a year, and going into that classroom was probably the hardest thing that I’ve ever done," Burns said. "There’s a total disconnect from any other experience." In interviews, Burns has cited the fact that during his first year of teaching 13 of his kids were shot. He said that the prevailing thought among his colleagues at Hamilton, which had a predominantly black student population, was: "You can’t do anything for these kids."

In the fourth season of The Wire, this is more or less the environment Roland Pryzbylewski enters. Played by Jim True-Frost, "Prez" is a reckless detective who has quit the force in shame after mistakenly shooting a black plainclothes officer. Seeking a redemptive career change, he takes a job teaching math at fictional Tilghman Middle School. Prez’s real-life alter ego had no classroom experience, but his wife taught in Baltimore for two years. True-Frost recalled Burns softly chuckling when she told a story about one of her fellow teachers saying, "I fought in Vietnam. This is worse."

At first, Pryzbylewski is overwhelmed. But he quickly learns the truth: "The system," True-Frost said, "is stacked against the really poor kids." When Michael Lee (Tristan Wilds), Namond Brice (Julito McCullum), Randy Wagstaff (Maestro Harrell), and Dukie (Crawford) enter Prez’s orbit, they’re already in trouble.

"The challenge of turning them around at the age that we meet them is Herculean," Burns said. "If you’re not going to invest in the most formative years of your life, zero to 3, there’s so much damage done. That damage just becomes more intense as they walk the road of poverty."

The bright but shy Dukie lives with his addict parents in a house with no running water. It’s implied that the cerebral and brooding Michael has been abused by his stepfather. The resourceful Randy, who sells candy to his schoolmates, is in foster care. The group is rounded out by the defiant Namond — the son of incarcerated drug enforcer Wee-Bey Brice — who’s constantly disrupting class.

The four teens join together to navigate life in West Baltimore. If their onscreen bond felt real, that’s because it was. Their friendship was forged long before the fourth season began filming.

Back in the mid-2000s, before auditioning for a television role, Julito McCullum had to fill out a background information form. One question stumped him: "What’s your favorite TV show?" Unsure what to write, he asked his mother, who said, "Just put The Wire. If this show ever gets kids, you have to be on it."

Two weeks later, the teenager from Brooklyn was reading for Namond. On that day, McCullum remembered, Simon was wearing a purple Baltimore Ravens jersey. "I was petrified," McCullum said with a laugh. "David looked so mean."

Still, McCullum landed the part, and soon he was in Baltimore shooting with the cast. Well, not exactly. First, Wilds — at 16, the oldest of the bunch — McCullum, Harrell, and Crawford spent about a month at The Wire’s new production office in Columbia, Maryland. There they attended a makeshift version of school. "It was like camp," McCullum said. The quartet passed the time by watching Family Guy and Anchorman, playing basketball at a nearby rec center, and getting lost on the internet. Harrell even helped McCullum set up a Myspace page. (Remember: This was 2005.) As with any group of friends, there was occasional in-fighting. "Jermaine got it the hardest," Harrell said. "He was the youngest. I gave him a ton of shit that wasn’t warranted." Said Crawford: "It was very tough."

Their education also included sessions with Robert Chew. The late Baltimore native, an actor and teacher who played drug kingpin "Proposition" Joe Stewart, worked closely with the show’s four young leads. He gently guided the teenagers through sad and emotionally complex scripts. "He helped us get past layers of discomfort," Crawford said, "and made it as easy as possible to get to the place we needed to be."

"The kids would be so solicitous of him," Burns said. With Chew, Burns added, the teens "formed this bond. Each one would say, ‘You could do it this way,’ or, ‘You could try that.’ They went in with a real strong idea of how to play the scene."

Without Chew, McCullum says he isn’t sure that he would’ve been able to bring Namond to life. To his pupils on The Wire, Chew was more than just a mentor. "He got us to understand," McCullum said, "what this whole thing was about."

As the fourth season unfolds, Prez begins to understand his surroundings. "Knowing who Pryzbylewski is, he couldn’t come in and be a dominant individual," Burns said. But realizing that his bosses’ directive to focus on preparing his classes for state standardized testing isn’t the least bit effective, the teacher changes his approach.

"If you have a lesson plan and it fails and you blame yourself, you’re on the road to becoming a good teacher," Burns said. "If you blame the kids, you should find another job. And what Prez did was say, ‘Why did I fail? Why didn’t I reach them?’"

To engage his own classes, Burns knew that he had to be creative. "I was teaching seventh grade with kids who were reading on a first-grade level," he said. "So talking any type of history is kind of meaningless. You adjust." So he ordered gallons of Elmer’s Glue and thousands of popsicle sticks and led basic engineering projects. "The kids loved that," Burns said. "It was hands-on and it was something they’d never done before, which is get out from underneath the desk."

In The Wire, Prez learns that his students like to shoot dice. To the surprise of his colleagues, he uses the game to teach probability. He also has his kids measure their height and wingspan and sets up a computer that’s been dug out of storage. Adapting new methods results in a handful of positive developments.

While still cold to Prez, Michael proves to be excellent at math. Dukie, who his teacher discreetly gives clean clothes and food, shows off his computer skills. And when Randy figures out that bulk candy can be purchased cheaply on the internet, he lights up and successfully asks Prez to order him some with a credit card.

Meanwhile, Namond is pulled from class and placed in a room with nine other similarly disruptive students. The trial program, co-run by Howard "Bunny" Colvin, a former police officer with an eye for reform, considers the needs of adolescents whose behavior is rooted in trauma. Gradually, some of the kids start to show progress.

The gains, however, are mostly confined to the classroom. As Burns reminded me, a typical school day is just six hours. And depending on the district, kids are in class for only about 180 days per year. "That leaves an awful lot of time when they’re not in school," Burns said. For Michael, Namond, Randy, and Dukie, that’s a problem.

It’s easy to forget that in the premiere of the fourth season, the four young leads are actually enjoying their last days of summer vacation. A portion of the episode revolves around the boys peeing in water balloons and throwing them at neighborhood bullies. The plan backfires, Michael gets beat up, and Namond treats everyone to ice cream. (Harrell recalled that during the filming of that scene, McCullum teased him about Randy’s choice of frozen treat: a comically giant multicolored popsicle.)

If there’s any innocence left in their world, though, it soon fades. The fate of the kids encapsulates Simon’s we-are-not-going-to-be-all-right ethos.

After delivering a seemingly innocuous message for the drug dealer Little Kevin, Randy learns the message has led to the murder of a rival dealer. Randy is soon overwhelmed by the burden of his secret. While attempting to get out of trouble at school, he tells the assistant principal — and then the police — what he knows. Then, after boneheaded detective Thomas "Herc" Hauk mistakenly lets Little Kevin know that Randy has been questioned as a witness, word gets out that he’s been talking to the cops.

Randy takes a beating at school, prompting Sergeant Ellis Carver to assign a police detail to the teenager’s foster mother Miss Anna’s place. Unsurprisingly, the detective’s assurance of safety is hollow. When someone phones in a false report of violence against a cop, the on-duty officer drives off. At that point, teenagers firebomb the house, leaving Miss Anna in critical condition with second- and third-degree burns.

This leads to one of the most memorable and gutting scenes in TV history. When Carver visits Randy in the hospital waiting room, the boy understandably doesn’t want to hear the detective’s apology. "You gonna help, huh?" Randy says as his voice rises and Carver walks away. "You gonna look out for me? You gonna look out for me, Sergeant Carver? You mean it? You gonna look out for me? You promise? You got my back, huh?"

True-Frost called Harrell’s performance "absolutely devastating." His goal, Harrell said, was to "channel the feeling of abandonment." As a result of the failures of a series of adults in his life, Randy is placed in a group home, where his reputation as a snitch results in more beatings.

Michael, on the other hand, is in a different kind of trouble. Not sure how else to deal with his abusive stepfather, he asks drug kingpin Marlo Stanfield for help. Stanfield’s top enforcer, Chris Partlow, then brutally beats the child predator to death. In exchange, Michael begins working for Marlo.

Meanwhile, Dukie is subject to a midyear promotion to ninth grade. Uneasy after being prematurely removed from an environment in which he was starting to succeed, he quits high school before his first day even starts. When Dukie’s family is evicted yet again, he moves in with Michael and his little brother Bug, for whom Marlo has rented an apartment.

"Michael was the smartest of the group," Burns said. "And he read the way the world was and he adapted to it. The really good drug dealers see at a very early age which way to fly, you know? In a different era and a different place, these guys probably would’ve been our robber barons or our Goldman Sachs people. In their world, it’s drug dealing. There’s no other occupation that you can depend on. That was Michael."

And then there’s Namond, who finally realizes that the game isn’t for him. Soon after he gives young subordinate Kenard drugs to sell, the aggressive pipsqueak claims that the cops took the stash. After realizing that Kenard is lying and has kept the package for himself, Michael beats him bloody. When Michael tells his friend to take back his package, a disturbed Namond can only muster four words: "I ain’t want it."

It took years before McCullum understood the significance of the line. "This is the moment he decides to verbally say, ‘I don’t want this life,’" McCullum said. "That’s the one scene I’ll never forget. It will remain with me for the rest of my life."

Namond later breaks down, telling Carver and boxing gym owner Cutty — a former gangster — that he isn’t fit to follow in his dad’s footsteps. "That ain’t in me," Namond says. Bunny Colvin, who months before had recognized Namond’s smarts and sense of humor, eventually receives Wee-Bey’s blessing and adopts the boy. In the universe of The Wire, it’s a rare happy ending.

"Three of them fell, one got out," Burns said. "You’ve got a 75 percent failure rate. That’s probably low."

As the fourth season comes to a close, the Baltimore school system is facing a $54 million deficit. Despite the shortfall, new mayor Tommy Carcetti — who already has his sights set on Annapolis and doesn’t want to alienate potential voters by taking taxpayer money — cynically refuses to accept funds from Maryland’s Republican governor. The mayor’s office also pulls the plug on Colvin’s program, dubbing it tracking. (This was the era of the No Child Left Behind Act.) When his co-researcher tries to tell him that academics will still take great interest in their findings, a frustrated Colvin asks, "When do the shit change?"

Burns knows that there’s no quick fix — the real-life Baltimore school system recently faced a $130 million budget gap — although he’s certain that addressing poverty would help. With financial security, Burns pointed out, parents can spend more time with their children. And as a result, it’s likely that fewer kids end up like Michael, Randy, and Dukie.

"For reasons that are both economic and political, we don’t want to look at poverty," said Burns, an advocate for a universal basic income, a policy that President Nixon twice tried to institute. "We don’t want to go down that road. Because it is so profound, so life-altering, that to change it today, under the rules that we’ve created, would be impossible."

The Wire doesn’t provide an answer to Colvin’s question, but 15 years after its debut, the show remains powerful for even having the audacity to ask it. McCullum said he still hears from teachers about the fourth season. "Thank you for actually shining a light on the city school system," McCullum remembered one saying. "Not many folks know that the problems are real." A fan once told Harrell that the show is the reason he became a social worker. And people continue to approach Crawford and tell him that they grew up like Dukie. "It’s just like, holy shit," Crawford said. "It was not my story. I’m truly privileged to be able to tackle that character."

Wilds, McCullum, Harrell, and Crawford all have spent the last decade successfully navigating show business, but they know that they’re inextricably linked to The Wire. Nine years after the series went off the air, it remains uniquely relevant. In that, there’s both beauty and shame.

"This story’s happening right now to someone," Harrell said. "It ain’t been fixed."

You can stream the entirety of The Wire on HBO GO and HBO NOW.

Disclosure: HBO is an initial investor in The Ringer.