Soap bubble isn't ready to burst yet

But fast forward to 2007 and the twice-weekly soap set in the fictional Glasgow suburb of Shieldinch has defied its critics, attracting an average of nearly 600,000 viewers a week as it prepares to celebrate its fifth birthday.

Though it is set on the west coast, the first words in the debut episode on 24 September 2002 - "The wedding's off" - were uttered by actor Eric Barlow from Comely Bank. Eric played Tommy Donachie, the landlord of The Tall Ship, who met a tragic end at the hands of the Shieldinch strangler.

Since then, ever more daring storylines have seen characters confined to wheelchairs or become infected with HIV; a fatal caravan explosion; and Stefan Dennis, better known as Neighbours' Paul Robinson, enter the cast as rapist Marcus McKenzie.

The series, devised by playwright Stephen Greenhorn, began with just 24 actors. Five years on and the BBC One Scotland soap has employed 212 actors - not including extras - many of whom have hailed from the Capital.

One of the best known is Eileen McCallum, a stalwart of Edinburgh's Royal Lyceum, who played High Road postmistress Isobel Blair and has lived in the Capital for more than 40 years. In true melodramatic soap style, the first of two anniversary episodes on Friday sees Eileen hit her son Archie, who has been having an affair with Niamh, over the head with an urn containing his father's ashes. He falls into the fireplace with blood pouring from the back of his head and she can't find a pulse.

So Eileen, is Archie dead? "You'll have to wait for the next episode to find out, but it's not looking good at all," replies the veteran actress coyly. "He's been so awful that something bad was bound to happen."

Eileen, from Bellevue, has been in the show for nearly two years, as the uppity, bigoted and vitriolic Liz, a role she relishes playing. "I got the script sent to me and I laughed so much - she was such a snobby cow," giggles Eileen.

River City is filmed at a specially created set in Dumbarton consisting of four tenements, a pub, shops and a boatyard. Despite being set in a Glasgow suburb, Eileen believes River City is relevant to Edinburgh people. She realised just how much when a woman approached her in the street, tapped her on the shoulder and said: "Don't worry I'm on your side."

Other Edinburgh actors to appear in River City include Phil McKee, 43, from Meadowbank, who enjoyed a recent stint as Shona's old flame Tony, and Julie Coombe, 39, of Davidson's Mains, who made her debut last March as Terri - a mother-of-four who will do anything to get her man.

Niddrie's Billy McElhaney plays Terri's love interest Jimmy Mullen and has been in the show for almost two years. The 50-year-old, who starred in award- winning play Gagarin Way, believes River City is a source of national pride.

Billy's character started as a thug, then fell for Scarlett, and is currently in a wheelchair after having been in a coma. "My storylines have been fantastic," he says. "The wheelchair gives us a licence to discuss the issues around disability."

Executive producer Sandra MacIver says she made a conscious decision a few years ago to include more east coast cast members. She says: "There was a feeling that people from the area felt excluded and this was the last thing we wanted. Now the show has a very strong Edinburgh presence amongst the cast - in fact actors from Edinburgh take up a lot of the screen time at the moment."

Jaclyn Tse is about to complete her first year playing River City medic, Dr Mai Lau. The 35-year-old actress, from Brunstane, says winning a part in the Shieldinch soap is a godsend for an actor.

She says: "I was 18 months between meeting the casting director and getting the part, which shows that they are very careful about their selection. Being in River City raises your profile and it's pretty prestigious because of that."

A River City fan herself before she got the part, Jaclyn is convinced the soap's strength lies in its hard-hitting storylines. "It's changed a lot in the last five years. They discuss everyday issues like racism, have had a lot of ethnic minority actors and are not afraid to tackle issues. That's what attracts the viewers and it's challenging for actors."

Racism came up in a recent storyline involving Dr Lau, when Tina's son Paul said he didn't want to be treated by a Chinese doctor. For Jaclyn, whose parents moved here from Hong Kong before she was born, it's a topic of which she has personal experience. "I was a victim of racism at school, when boys used to make snide comments about me," she says. "But it made me stronger as a person and more determined to succeed, so it had the opposite effect. In River City my character also takes it in her stride. Like myself, she's mature enough to handle it."

Jaclyn's first scene last October was with Eileen's character Liz, who had come to the doctor's surgery complaining of feeling clumsy and forgetful and Dr Lau had to tell her she was being drugged. "I'd seen her in a lot of plays and on television so it was quite daunting. But she has years of experience and was brilliant," Jaclyn enthuses. Clearly very happy travelling regularly to Dumbarton for her role in River City, Jaclyn speaks warmly of the atmosphere on the show.

"I've been surprised by what a big family it is. People get together and try to socialise and you know the door is always open if you have any issues to discuss. Everyone is so supportive, right through to the top."

Eileen agrees wholeheartedly. She believes the success of the show lies in the strength of the writing and the tight cast and crew, for whom she has nothing but praise, particularly the makeup artists who transform her into her well-groomed character.

As the end of the cast's summer break approaches, Eileen has seen the new scripts and can't wait to start filming again. "I'm proud of it," she declares. "I'm confident that it has a long future. The scripts are great, there's a great atmosphere and we have a great bunch of directors. I couldn't be happier."

• The River City anniversary episodes are on Friday at 8.30pm and Tuesday, September 25, at 8pm on BBC One Scotland