NEW YORK (AP) — Walking back to his trailer while shooting the first season of “The Wire”, Andre Royo was still in character as the homeless junkie and informant Bubbles — face scarred, hair a craggy black mess — when a real junkie approached with what Royo calls his “Street Oscar”.“He said, ‘Yo, you need this, man. You look like you need a hit’,” recalls Royo. “I laughed a little bit and I got emotional. I was like, ‘Wow, he thinks I’m a junkie for real’. I felt validated.”

Royo had to discard his “Oscar” before flying home (airlines might not recognise a bag of heroin as an acting trophy), but the gesture was reward enough for Royo. It’s also about as close as any actor on the acclaimed HBO series has come to awards recognition, even though the Baltimore drama has been hailed with hyperbole by critics.

On Sunday, Bubbles serves as an unusual reservoir of humanity as “The Wire” airs the fourth season’s finale (11 p.m. Bermuda time). Bubbles has long been one of the show’s most moral characters, captivating in his struggle to fight addiction and hopelessness on a show that revolves around futility.

This season has focused on a handful of young teenagers in West Baltimore’s broken school system. The final episodes find various characters fighting for the futures of the kids — and none is more affecting than Bubs’ unlikely mentoring of a homeless boy, which plays out tragically.

Bubbles’ emotional scenes represent a climax for both the character and Royo, who has taken a role originally meant for just seven episodes and made it one of the show’s most popular. But as always on “The Wire” — be it politics, police bureaucracy or the code of the street — Royo’s acting career has been a long road of playing “the game”.

The 38-year-old was raised in the Bronx, New York. After high school he wanted to act, but he had no idea how to pursue that career — all he had heard on TV were stories of various stars being “discovered”. So he spent two years “just hanging’ out in Manhattan” at the clubs, dressing weird, hoping that someone would “discover” him.

Royo eventually found acting classes, which led to off-off-Broadway plays, a job in TLC’s “Ain’t Too Proud to Beg” video and a small part on “Law & Order”. His biggest breakthrough was a notable role in John Singleton’s “Shaft”.

Royo, whose father is Cuban, was often told he wasn’t “black enough for the black roles” or “Spanish enough for the Spanish roles”, and that he simply “looked Ethiopian”. But he landed the part of Bubbles for the pilot of “The Wire” — not that he thought it was a big break at the time.

The dense plot and lack of standard cop show action made Royo think “The Wire” didn’t have a chance. Besides, he says, “You get nervous. You go, ‘How can I make this character not cliche?’” So he spent time with junkies in New York and Baltimore — and found that every junkie is different.

“They were very stern on making sure that if you’re a heroin addict, you’re not a cocaine addict — they act differently,” he says. “At the end of the day, it helped me remove myself from trying to find certain tricks and just be me.”

Like so much of “The Wire”, the character of Bubbles was taken directly from the street. Ed Burns, who helped create the show with David Simon (a former Baltimore journalist) and writes many of the episodes, was Baltimore police for years (later becoming a school teacher). For 15 years, Bubbles was one of his best informants.

“In his prime, whatever happened in West Baltimore, he knew about,” Burns says of the real Bubbles, who he remembers fondly as an honest, unique person. “There’s a lot of honour in the game, you just have to find it and sort of cultivate it.”

When Bubbles died of AIDS in the late 1980s, Simon wrote an obituary for him, but without Bubbles’ name because his family wanted it kept anonymous. Burns still recognises Bubs in Royo’s performance.

“Andre has a very Chaplinesque way of being,” says Burns. “There’s a little walk that he does after the first time he’s robbed and the guy takes his shoes off and takes the drugs. He picks himself up and he walks over to the cart and the kids laugh at him. That wasn’t in the script — that was something he did as an actor. He looked like Quasimodo.”

Burns largely credits the appeal of Bubbles to Royo’s sympathetic portrayal.

“It’s this feeling of loss that you have when you see a human being with such potential trapped in this world. He’s more of our conscience,” he says. “You can feel comfortable writing anything for (Royo). You know he can reach it.”

At the same time, it’s easy to wonder if the potential of Royo and much of the ensemble cast has been largely untapped because of either casting directors’ unwillingness to try the actors in different roles or because of a subtle racist disinterest for a largely African-American programme.

“After the first season, I got a lot of being-on-cocaine, being-on-meth” roles offered to me, says Royo. “Did it bother me? Not at all. I was stereotyped when I was waiting tables.”

“You got to show Hollywood that you can play the game,” he says. “I’ll come into every scene or character 100 percent, and sooner or later, good acting will transcend.”

Having moved with his wife and daughter to Los Angeles, where they have opened a restaurant, Royo is understandably ready for some new challenges.

“I’ve been snitching for a long time now. The first job I had on ‘Law & Order’ I was snitching,” he says, also citing his roles in “Third Watch” and “Shaft.” “For some reason, they look at me and think, `That (guy) will tell. ... But I am Bubbles. There’s a part of me that’s invested and I want to make sure his story is fully told.”

Royo is also disappointed that more of the mainstream media hasn’t paid attention to his castmates — no late shows, no Oprah Winfrey.

“It’s our loss,” says Burns, citing the talent of Royo and a dozen other actors on “The Wire”, from Michael K. Williams (Omar) to Wendell Pierce (Bunk Moreland).

“These guys clearly cut the mustard. They can act with anyone,” says Burns. “I don’t know why it has to be this ‘You can play a drug addict; you can play the good sidekick.’ These are the roles that these actors end up doing and it’s a shame.”