Earlier this year, Ralf Little, best known to us as Antony in The Royle Family, set off for Hollywood. “I didn’t make a big thing about it,” he says now, perching over a cup of tea, “but I had the best time.” Between football appointments with Robbie Williams for Hollywood United and rolling around his pad in the Westwood Hills (“I chucked a bit of money at it, because I wasn't expecting to enjoy it, to be honest,” he says with characteristic northern bonhomie), one appointment with producers took his fancy. “I just thought,” he says of the internet weblog-drama KateModern, “that it was a really sexy idea.” And he was right.

KateModern is at the vanguard of a fresh, new and brilliantly interactive form of storytelling. They’re calling it “Snack TV”, but you might prefer the expression “Freality TV”, as this new medium blurs the lines between fiction and reality.

Delivered in bite-size daily chunks of just a few minutes, and swiftly hot-wired through the social-networking site Bebo, the “webisodes” of KateModern follow the lives of four modern twentysomethings. Kate is a struggling art student and “highly pretentious” flake. Charlie is a free-spirited, cute Aussie nomad. Her boyfriend, Gavin, played by Little, is a dark, partially disturbed character. Meanwhile, Gavin’s best friend, Tariq, bears the brunt of everybody’s personal fallouts.

In the furiously competitive world of social-networking sites, the series brilliantly knits Bebo’s community together and drags in new punters every day. It’s got the 11-to 24-year-olds in thrall. The action is filmed mostly in east London, in the kind of hip and knowing way that EastEnders can only dream of. It is heartfelt fiction with a side order of fantasy sequences, hidden cults, dramatic twists and familiar twentysomething relationship woes. And it is a huge success with its fickle, restless target audience, more accustomed to bespoke viewing courtesy of YouTube than being prescribed to by out-of-touch television commissioners searching for the lowest common denominator. It has attracted no fewer than 30m views worldwide over the past three months.

We just don’t watch TV in the way we used to,” Little explains. “Get used to it. There isn’t a moment where you think, ‘Ah, it’s Tuesday night, it’s 9pm, it’s X-Files.’ You might watch a DVD box set or organise your own viewing with Sky+. This just seemed like a brilliant extension of that.”

To invigorate the mix-up of fiction and reality, each character has a Bebo home page – as does each actor. (Little drops into his constantly.) While long-term story lines are in place, the audience is encouraged to shape the storyboarding via posts to the characters. “The characters are making decisions based on what their friends are telling them,” Little explains, “though, in this case, their friends are also the viewers.” It’s testament to the audience’s net savvy that they can delineate the distinction on the flip of a fivepence. “You’ll get somebody writing ‘Don’t do that!’ on Gavin’s home page,” Little says. “Then, five minutes later, the same person is on mine saying, ‘Great show, by the way.’ ” This is causing all sorts of consternation for the television industry, which is slowly hanging itself with its own rope by searching out ever more creative revenue streams to make up for advertising deficiencies. But they should have seen it coming: KateModern was commissioned following the unprecedented success of the American snack-TV smash Lonelygirl15, which started out as a blog that everyone thought was for real. In its wake came the equally successful Quarterlife, about a group of American 25-year-olds having their own individual crises through the blog. “They’re just very, very good ideas,” Little says.

It’s a canny move for Little to become the most famous face on snack TV. “There was a tiny part of me that thought people would say, ‘Oh, he’s doing that because he can’t get any “real” work.’ But the reason I’m doing it is that it’s so exciting to be in there right at the beginning.” After roles alongside Kevin Spacey in the forthcoming Joe Meek biopic, Telstar, and a well-received one-hander on the West End stage in Stacy, Little says that Hollywood was a turning point for him. “It just taught me not to sit on my arse and wait for things to happen. It was about getting involved and taking a chance on things.”

Not that this is the first time he’s been associated with pioneering broadcasting. The Royle Family was made back in the days before the British not-com (real-time sitcoms without laughter tracks) was even a twinkle in Ricky Gervais’s eye, let alone the thing he would take as his own.

“I’m glad you said that. I mean, of course The Office is brilliant, and Ricky Gervais is very kind to the show about acknowledging the debt, but The Royle Family does tend to get overlooked when it comes to comedy greats. The year we finished it, you’d walk past WHSmith and there’d be a Christmas display of books in the window saying, ‘All-time comedy greats’. The three people on the cover would be Basil Fawlty, Del Boy and Jim Royle. One year later, you’d walk past and it was Basil Fawlty, Del Boy and David Brent.”

This time, he knows it’s for real.

“I had a moment at a party last week when the cast were introduced as being on the most successful internet TV show in the world. You can’t take that stuff away, really.” He looks justifiably chuffed with himself. KateModern was a very good call.