Since its foundation in 1884 in Leeds by a Jewish refugee from eastern Europe, this company came to be loved and respected like an indispensable part of the family. Everyone had an opinion about its food, its clothes ranges.

You couldn't avoid it. Even if you didn't shop there as a teenager, half your deliveries from Santa every December would bear a St Michael label. So when the company falls on hard times, it is rather like the feeling you get at the end of rousing tragic theatre. When Hamlet or Othello bites the dust, you feel that part of you has gone with them.

I guess anybody at the BBC watching me parade across the fourth floor of the office in my battered old jeans and less than trendy woollen sweaters would conclude that I would be the least suitable producer to make a programme about a huge retail outlet that had lost its way in the fashion stakes. "Fair point, guv", I would reply, but with two caveats.

First, my mother ran a ladies' dress shop in Bolton for more fifty years, so the need to surprise and please the customer has been imprinted on my brain through her savvy business sense, since my primary school days. And secondly, what has happened at Marks and Spencers in recent years isn't just about calling the shots in the fashion stakes. The story of M&S has more in common with classic Shakespearean tragedy than it has with its neighbours on the high street like C&A and Debenhams.

What has emerged from speaking to hundreds of customers, sales assistants and directors of M&S in recent months is that there is a very real sense that the company was held in such high esteem, that its difficulties are felt very personally and very deeply. I sense, still, a very deep desire on behalf of the British public, to turn things round and revive the brand.

If the M&S story is a tragedy on Shakespearean lines, what was the company's tragic flaw? A story told by a number of former M&S insiders from the 1990s illuminates our understanding.

The now firmly established sandwich and food outlet, Pret a Manger, was expanding throughout London. Senior executives at M&S had noted this and voiced alarm at the way in which the food was being presented in a slick, efficient and attractive manner.

M&S's own food was doing very well and therefore it was felt there was no need to worry about Pret's advances in the market. "But wouldn't it be better if we had our own scaled down equivalents in the high street," a number of insiders said, "instead of making people fight their way down through the clothes, down the steps and past all the lunchtime crowds?"

Such views did not prevail. Pret a Manger's advance continued. One of the key interviewees in the Money Programme item, Brian Godbold, the company's Design Director from 1993-1998, makes the telling point that "what is the right decision for today isn't necessarily right for tomorrow."

And when your company is pulling in profits of more than a billion pounds a year, as it was in 1997 and 1998, the appetite for strict self-criticism and innovation, so indispensable to success, must almost inevitably be hard to sustain. But as the old business and industrial expert and guru, John Harvey-Jones, used to say to his Troubleshooter clients: "Change or die."

Easier said than done. The high street was moving more rapidly in fashion and store layout in the mid to late nineties than ever before and Sir Richard Greenbury and his board probably had a greater task to stay ahead of the competition compared with any previous M&S chairman and his board. Yet the signs and warnings were there.

Documents obtained by our programme conclusively show that customers' faith in M&S was being eroded well before the recession of late 1998 that hit the high street, dented profits and contributed to M&S' ignominious attempted boardroom coup and feuding. Once that news leaked out, the brand was in serious trouble. For most punters, it would have been like coming across hitherto angelic and perfect parents throwing plates at one another in the kitchen.

Bold new initiatives have been taken, but tinkering with brand identities can be dangerous after they have been built up over so long a period. Luc Vandevelde, the chairman, has given himself until February 2002 to try and turn things round. He will hope upcoming trading figures are the nadir. Roger Holmes, the new head of retail, joins from the Kingfisher group on Jan 1. In 2001, great things are expected.

Mark Dowd, Producer