By Keily Oakes BBC News entertainment reporter

Dirty Den uttered the first line on the soap 20 years ago

EastEnders' Dirty Den has been killed off once again to mark the soap's 20th anniversary, in a bid by the show's producers to stall flagging ratings.

Dirty Den launched the show back in 1985, eloquently announcing "stinks in here" on entering a flat in Walford's Albert Square.

EastEnders was the BBC's first primetime soap and the corporation faced criticism for funding such mainstream, and some believed lowbrow, entertainment.

It took about six months for the show to take off as people did not know what to make of it. But the soap found its feet and regularly began attracting 20 million viewers.

Affairs, rape, murder, marriage, drugs and incest have become staple fare for the residents of the fictional East End borough of Walford

Over the years, viewing figures have gone through inevitable peaks and troughs, but the past year has seen the show at a low ebb.

Much of the recent criticism was levelled at the producers' decision to extend the soap to four nights a week.

However, All About Soap editor Jonathan Hughes does not believe this is the nub of the problem. He says the first year the show went four nights a week, it was a huge success but the momentum has not been sustained.

Kat and Alfie's wedding signalled a high point in EastEnders' ratings

He also points out that when Emmerdale began broadcasting six nights a week, it strengthened the popularity of the ITV show.

According to Mr Hughes, while EastEnders' ratings have fallen, talk of it haemorrhaging viewers is exaggerated. When the week night episodes are factored in with the Sunday omnibus, the show is still achieving impressive ratings.

Realistic characters

"But the critics and fans have been less than happy with the direction the show has taken in the past year," says Mr Hughes. "They feel cheated by the storylines."

"Feedback from our readers suggests they do not like the gangsters, murders and violence. They want couples, relationships in crisis and characters they can relate to like Little Mo and Alfie.

"Producers must remember that women viewers are central to soaps."

EastEnders recently underwent an upheaval behind-the-scenes. Following the departure of executive producer Kathleen Hutchison and series producer Sharon Hughff, John Yorke - the man who introduced the Slater family to the show - has been brought back.

Female viewers prefer down-to-earth characters like Little Mo

Den's murder, produced by Hutchison, has pumped new life into the show - with a trio of vengeful women in the frame to bump him off.

An EastEnders spokeswoman called the anniversary edition "the climax of some of the show's most explosive storylines for a very long time".

Tarnished reputation

Dirty Den, played by actor Leslie Grantham returned to the show in September 2003, having been supposedly killed off in 1989.

But this time he leaves not as the character everyone loves to hate, but one that it seems everyone simply hates, following a sordid storyline in which he impregnated his son's 21-year-old girlfriend.

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Grantham's off-screen shenanigans have not helped his profile either.

"People feel cheated by the Den storyline. He has not fitted in, and he has just become too nasty," said All About Soap's Mr Hughes.

"It is a shame that the character has been tarnished because Den was such a well-remembered character. But back then he was part of a couple, Den and Angie, on his own it didn't work."

EastEnders has long battled ITV rival Coronation Street for soap supremacy. Just two years ago, the BBC soap was sweeping the board at the National TV Awards with Kat and Alfie named the nation's favourite soap couple.

Hillman's demise pulled in over 19 million viewers in February 2003

Indeed in 2002, flagship ITV soaps Coronation Street and Emmerdale were snubbed by the Royal Television Society in favour of Doctors and Hollyoaks, and the Street was falling behind in the ratings war.

But while EastEnders has been panned by the critics in recent times, Coronation Street has got its act together, spearheaded by the Richard Hillman serial killer storyline.

The Weatherfield soap traditionally attracted an older audience, but the arrival of some younger characters and headline-grabbing storylines means it now appeals to a much broader audience.

"EastEnders certainly has had a rough year, but I think it will pick up if it address certain issues. Saying that, if it continued its downturn for a couple of years then it should not be impervious to the axe," said Mr Hughes.