Those of you who haven’t watched the first two series of the RTÉ crime drama Love/Hate might be confused about what it’s actually about.

Its press photos (used here) have been lampooned for representing Dublin gangsters as dishy boyband lookalikes (indeed, those who’ve dipped in only briefly, might be forgiven for thinking it was a docudrama about One Direction going off the rails). It was also initially condemned for its apparent glorification of gangland. Many reviewers claimed to hate it. However, there’s a fine line between hate and love (literally in the case of Love/Hate) and by series two, because RTÉ stuck with it, and because it’s genuinely very good, many haters revised their opinions.

Love/Hate is the best drama RTÉ has produced. Created by writer and former Last Word producer Stuart Carolan with director David Caffrey, Love/Hate tells the story of feuding inner-city gang members and their wives, girlfriends, drug-connections and victims. The penultimate episode of last season pulled in an average of 659,000 viewers to watch brooding, morally-conflicted Darren, aka Robert Sheehan, knock-off paranoid, shifty-eyed crime boss John Boy, aka Aidan Gillen. (Both actors are, incidentally, internationally successful sorts, not usually found slumming it at the national broadcaster.)

What’s different about it? Well, we’ve come a long way since the 1978 drama The Spike was taken off the air because it featured a naked lady. Love/Hate not only features naked people, but recreational drug-taking and ultra-violence. If you happened to think RTÉ was still following the educational template it set with The Riordans, a programme partially designed to teach viewers about modern farming methods, you’d assume that Love/Hate was produced to teach us about new-fangled drugs, sex-positions and murder techniques.

This filth didn’t come from nowhere. “I remember coming home from England and being surprised at the nudity in the first episode of Raw,” says softly-spoken ac-tor Tom Vaughan-Lawlor, sounding nothing like his character, rising crime-boss Nidge. “I think things had already changed a lot. Saying that, I think the first series of Love/Hate was a slightly watered down version of what the second series was, and now I think we’re making the series that was in Stuart’s imagination. I don’t blame RTÉ for being cautious. It was an unknown entity and no one knew how it would be received. As it was, the Irish Times TV critic said it didn’t have enough violence.”

But violence, drug use and rumpy-pumpy do not in themselves a mature television programme make. Love/Hate is also a dark, thought-provoking drama littered with funny, characterful lines, subversive plot turns and wordless, musical montages. Even its minor characters feel like they have stories to tell. All of these features suggest that Love/Hate is made by people excited by the innovations of US telly.

The 21st century really is a golden age of television drama. Once upon a time the economics of serialised TV drama from the US was dictated by the need to please advertisers and pander to casual viewers. This meant you could never make plots too complicated or allow your characters to learn anything.

The A-Team, for example, was reset to basics at the beginning of each episode. The backstory could be summed up in 30 seconds of intro credits. There was no character development, no long-term consequence, no story arcs. BA Baracus never got to the bottom of his fear of flying. Cigar-chewing Hannibal never got emphysema. Howling Mad Murdock never made any progress with his mental illness (possibly because his friends kept breaking him out of hospital).

While some shows always pushed the boundaries of characterisation, plot and style (Upstairs Downstairs, Moonlighting, Buffy the Vampire Slayer), the big change came with the US subscription-based cable channels. By unshackling themselves from ad-breaks, HBO, AMC and the Sci Fi (now Syfy) channel freed a generation of television auteurs to say, in the words of Wire creator David Simon: “F*** the casual viewer.”

This movement was further driven by the rise of the DVD boxset and online viewing options that allowed TV fans to pick over the plot-points at their own pace and in their own time.

Medium of choice

Thanks to Mad Men, The Wire, The Sopranos, Deadwood and Battlestar Galactica, audience expectations were changed forever. Television became a writer’s medium. It, not cinema, is the moving-picture counterpart to the novel and telly fans soon expected the same consistency and coherence from television writing teams as they expected from novelists. This required a new kind of television producer: the show-runner, writer/producers such as David Chase on The Sopranos, Joss Whedon on Buffy the Vampire Slayer, and, yes, Stuart Carolan on Love/Hate.

Carolan is essentially RTÉ’s first show-runner. “Stuart is an executive producer on Love/Hate,” says Jane Gogan, commissioning editor of drama in RTÉ, “which is the first time RTÉ have had a writer as executive producer, at least in my time. The show is very much defined by Stuart, whereas something like The Clinic or Raw would have a completely different approach.”

To be fair to RTÉ, the programme didn’t come out of a vacuum. The station hasn’t done badly over the past decade. Drama is an expensive, risky proposition and the national broadcaster is expected to please all the licence payers, all the time. After a patchy period in the 1990s, it has, in the 21st century, produced standouts such as Bachelors Walk, Pure Mule and Prosperity. “TV drama is a young medium in Ireland,” says Gogan. “We’re building a new tradition.” This new tradition will only be facilitated by a willingness to spend money and to take risks, and created by people who take television drama seriously as a medium in its own right, not just frustrated filmmakers or slumming-it theatre folk.

“It’s funny to see movie actors fighting to get into TV shows when it was always the other way around,” says Tom Vaughan-Lawlor. “It’s because the story and the exploration of characters can take place in such depth over the course of a TV series. It is like a great novel. You get to explore the massive arc of a character in a way you can’t condense into two hours of a movie. America’s had this golden age of TV. I think now we’re starting to hit that bar in this country.”

Meet the show-runner: Stuart Carolan

Is it a golden age of TV drama?

Most people do the boxset thing now . . . I like Homeland and Breaking Bad . . . I think American drama has influenced everybody. I just got a boxset of the French drama Braquo. I liked the Israeli version of In Treatment. I don't know if it's a golden age, but I think it's fantastic

RTÉ has given you a lot of freedom.

HBO shows can have a certain level of bad language or violence you don't get on network television. RTÉ 1 is the equivalent of a network channel and yet they've let us do things you just wouldn't see on BBC1 or ITV. Violence, sex and bad language aren't key to what we do, but we're allowed to do it because we're showing the truth . . . They know it's not about being exploitative.

There's a lot of attention to detail in the show.

I've a great team . . . [ director of photography] David Odd said he wanted it to look like a cross between Jack Vettriano and Vermeer.

Vermeer apparently loved light from the north, so not only did we need all sorts of strange locations but they also had to be north-facing.

Is there an end in sight?

I kind of have an end in mind but I don't want to say what it is [ Carolan has been given the go ahead for series four and is thinking of series five].

I don't know when I'll be working with people this strong and have this much support again.