There will be an outcry followed by a succession of inquests, public inquiries, perhaps even a Royal Commission. Politicians and the press will demand ministerial resignations and the multiple warnings made in the Seventies and Eighties about the inherent dangers in the new technology of swapping genes between unrelated species will be dug up and triumphantly flourished with cries of "You were warned."
People will recall the mad cow epidemic, which killed several hundred (it could be several thousand) people - most of them Britons - between 1995 and 2015. They will recite the old, old wisdom, that to go against nature is to invite calamity. Just as feeding the ground-up remains of dead cattle to live cattle was weird, wrong, asking for trouble, so too is shifting a gene which evolved in a bacterium or a plant into an animal - or vice versa.
They may recall a speech of King Charles, made when he was still Prince of Wales, to organic farmers in September 1996. "I believe we have now reached a moral and ethical watershed," he said. "What actual right do we have to experiment, Frankenstein-like, with the very stuff of life?"
But after a few weeks or months the fuss will die away. Why? Because society will quietly, grudgingly, accept that genetic engineering has become indispensable and that the benefits this technology has brought vastly outweigh the damages it has wrought.
By 2016 a vast range of gene therapies, drugs, industrial chemicals, food additives, crop plants and farm animals will be produced using this technology. The global turnover of these industries will have run into trillions of pounds and they will have saved or extended millions of human lives.
Genetic engineering was invented a quarter-century ago, mainly by US geneticists and biochemists. They developed a toolkit of enzymes and techniques for snipping DNA, the extraordinarily long hereditary molecule shared by virtually all life forms, in a predictable, repeatable way. They found out how to move fragments of DNA carrying entire genes between different kinds of bacteria and viruses.
The mind-boggling implications of this were instantly recognised. Mankind could take a selected attribute from one creature and transfer it to a completely unrelated one. Thus a bacterium could be made to make insulin, the indispensable human hormone which diabetics lack.
The dangers were also recognised at the time. What if a man-made organism also acquired a destructive attribute and was able to flourish, out of control? These fears led to a brief moratorium on genetic engineering research in the mid-Seventies.
Having satisfied themselves and governments that these fears were exaggerated, the researchers continued, aided by a flood of stock-market money pouring into the new genetic engineering firms. But making the new technology work turned out to be much harder than had been hoped.
Even the simplest bacterium is an extraordinarily complex machine. Persuading it to take in an alien gene from an unrelated species and incorporate it so that it was passed on from generation to generation was hard enough. Getting it to express that gene vigorously - using it to make copious quantities of the enzyme or hormone which the gene "coded" for and was the desired end product, was harder still.
Those difficulties caused delays and disillusion with the development of genetic engineering in the Eighties. Now, however, the new technology is rushing into our lives. There are dozens of products from medicine, agriculture and industry which rely on GMOs - genetically modified organisms. Already a variety of common food additives (vitamins, amino acids) across the Western world are made using GMOs.
And Europe is about to receive much more GMO food. For the United States, the country which has done most to develop the technology and debate its application, has decided to allow GMO varieties of two of its most important crops, sweet corn and soya, to be grown in large quantities for the first time this year. They have already been harvested, mixed with the ordinary kind of grain and bean and exported.
The European Union has licensed use of this soya, which has been modified to make it resistant to a weedkiller. It has not yet given approval to the genetically modified sweet corn, which belongs to the Swiss drugs and chemicals giant CIBA, even though it has now reached Europe.
Corn and soya are used in a variety of processed foods and the US is the biggest exporter of these crops - so very soon products with some GMO content will be splattered all over the supermarket shelves. Free trade and the American decision to embrace the new technology have made a mockery of the intention of Britain's supermarkets to label all foods containing GMOs because that is what their customers wanted.
Were they to stick with that policy, they would soon either have to label a huge variety of products or begin "negative labelling". That means sourcing products which have no GMO content, and declaring them as such. Because such products will soon be minority items, they will also become more expensive.
The large number of geneticists who have wanted the maximum of public information and debate about the appliance of their new science find this deeply frustrating. For years they have been trying to make the public and the press take an interest in genetic engineering, battling against the fact that you really need to understand molecular genetics to at least A-level standard to grapple with it.
There have been several symposia and exercises aimed at making ordinary people judge the new technology on an informed basis. But mostly the scientists and a handful of policy makers have encountered apathy and uninformed hostility from the public and press alike. And now, abruptly, genetic engineering has arrived in our midst en masse.
It sounds, and is, a regrettable state of affairs. But we ought to be optimistic about the abilities of our societies to handle new technologies. By and large, we embrace them only if the benefits outweigh the costs - and we also try, continuously, to reduce those costs. Think of the car as an example.
If a technology turns out to be a loser, we are also capable of rejecting it. Think of nuclear power, which is in retreat across most of the world despite decades of backing from the most powerful organisations in the world, the governments of nation states.
Genetic engineering will bring mishaps and stupidities in its wake. But, overall, it's highly likely to be a good thing, for which the benefits handsomely outweigh the risks. Enjoy the corn. Enjoy the beans. They may have been snuck in on us, but they'll still make a wholesome meal.