Rarely has a takeover battle produced so much pleasure. In the space of a few days, the supermarket group Safeway received a £2.9bn takeover bid from its rival William Morrison Supermarkets, and counter-offers from both Sainsbury and Asda. Suddenly, there is a scrap between three of Britain's best-known companies. This is fee heaven for investment bankers, who have been twiddling their thumbs for the past 18 months, poor loves. It is also great drama.

Not since Granada launched its hostile bid for Forte, catching the heir and chief executive, Rocco, with his pants down on a grouse moor, has everyone conformed so splendidly to type. All the main players are behaving in line with their regional or national stereotypes.

Thus we have Sir Ken Morrison - blunt, gruff, cunning and careful with his pennies - doing everything we should expect from a self-made Yorkshire billionaire. He donned pinstripes and red braces to present his bid to the City, but he might just as well have come down to London with a flat cap and matching whippets, so uncomfortable did he appear setting out his stall to the soft southern suits.

Enter Sir Peter Davis, chief executive of Sainsbury, patrician gent and bon vivant, who has moved effortlessly through some of the biggest boardrooms of Britain, urbane adviser to cabinet ministers and corporate princes. An affable cove over a private lunch table, he nevertheless conforms to northern views of southerners as smooth, arrogant and condescending. His description of Sir Ken on the Today programme as "an admirable grocer" sounded magisterially patronising.

Add in his penchant for fine wines and opera (he's on the board of the Royal Opera House), and the contrast between the two bidders could hardly be more pronounced. Imagine, if you will, Nicholas Soames and John Prescott squabbling over a trolley.

It gets better. Enter the Americans in the shape of Asda, which is owned by Wal-Mart, the biggest retailer in the world. The message from the boys from Bentonville, Arkansas, is: we're bigger and better than anyone else, and we're offering hard cash rather than inferior, pansy Limey shares (both Morrison and Sainsbury hope to use their own shares to pay for Safeway). Asda's chief executive is called Tony DeNunzio, who sounds like a tough young blade from the Bronx but disappointingly turns out to be an accountant from St Ives and a bit sad: his hobby, he says, is sampling Asda's range of ready meals.

We are still in Act 1. There is talk of sundry venture capitalists, and even a reinvigorated Marks & Spencer, joining the auction. In retail terms, this is an unrepeatable offer. Because of planning rules, such a plum portfolio of stores will never again come up for grabs.

Despite the money talk, the outcome will depend mostly on regulators and politicians. All three bids raise concerns about monopolies, though Morrison's could slip through without a reference to the Competition Commission. The story of food retailing in Britain has been of ever greater concentration. But so far, at least, there is no evidence that this has pushed up grocery prices. Three years ago, the commission, ordered to investigate "rip-off Britain" by the government, found that the price of food had fallen by 9 per cent in real terms over the previous ten years. It could find no evidence of supermarkets acting in an anti-competitive manner. If anything, the biggest players were using their buying muscle and other scale efficiencies to drive down prices.

It would be naive to assume that this increasing concentration can go on without the dwindling survivors starting to abuse their monopoly power. It is pretty evident that the tipping point is close. On the commission's rule of thumb that no one wants to drive more than ten minutes in town or 15 minutes in the country to do the weekly shop, many shoppers are already restricted on choice.

The other danger is that supermarkets screw down suppliers and farmers, leading to lower quality and less choice. The commission has, in the past, identified 30 ruses inflicted by the supermarkets on weaker suppliers, such as demands for retrospective discounts. Greater market concentration will increase the scope for this abuse.

There is one other bit player in the drama: David (Lord) Sainsbury, the science minister. His vast donations to Labour - financed by the dividends from his 13 per cent Sainsbury stake - make any government decision that bit more awkward. Patricia Hewitt, his colleague at the Department of Trade and Industry, will ultimately decide this battle. Of course it won't influence her one jot, but his lordship's personal shareholding has shrunk £93m in the six days since battle commenced, just through worries that Sainsbury could be the big loser.

Patrick Hosking is the deputy City editor of the London Evening Standard