Today, the talk of the town is adultery. Bill Clinton’s alleged adultery that is, and Robin Cook’s. The story which dominated the Falkirk Herald before Christmas - of the extra-marital affair between 49-year-old chemistry teacher Frank McCaffery and modern studies teacher Claire McKeown, 29, at the local Catholic high school, under the nose of Mrs Sonia McCaffery - is out of the headlines now. But for the staff and pupils involved, the repercussions continue.

Sonia McCaffery, 48, is back at the school - St Mungo’s -teaching English after almost two months’ absence late last year with “nervous debility”. Her daughter Elena, 17, remains at the school, too, about to sit her Highers, the Scottish equivalent of A-levels. Frank McCaffery continues to teach science at St Mungo’s, although his wife doesn’t speak to him any more. Claire McKeown is now working at nearby Denny High, a non-denominational school, after transferring at her own request from St Mungo’s - where she was a pupil before becoming a teacher - at the beginning of this term.

The situation, more quadrangle than triangle, split staff, outraged students and, reports suggest, seriously undermined the authority of at least two of the teachers involved. Yet it was resolved not by interventio n on the part of the education authority or senior management at the school, but by a game of brinkmanship involving pupil power backed up by the brawn of the popular press.

Sonia McCaffery is a smart woman in every sense. Vivacious and elegant, it comes as no surprise to learn that she has Italian blood from her mother’s side of the family. In her high-heeled boots and tailored skirt she would look more at home in downtown Rome than the York Caf. But here she is in Falkirk, assistant principal teacher of English at St Mungo’s, where she has taught for 23 years.

Her husband’s affair lasted for two and a half years. Sonia was one of the last even to hear about the rumours which had been circulating among staff and pupils, when in June 1995 she received an anonymous letter in her pigeonhole alerting her to her husband’s affair with the young woman who made a point of sitting next to her in the staffroom.

“I thought the letter was just a piece of nastiness,’’ she says. “I showed it to many other staff, but they all denied it. And I was assured by Frank, and by her, that this was all lies. I just believed him. Now I know how stupid I’ve been. But I did believe him.’’ So much so that, shortly afterwards, Sonia McCaffery and a colleague took a bucket of water out to the front wall of the school and cleaned off the chalk graffiti linking Mr McCaffery and Miss McKeown.

Sonia had been duped; Frank was having an affair, but it was to be more than two years before she discovered the truth. Her husband “roared out” one evening last October, having admitted that the rumours were true. The betrayal she has suffered is several-fold. Not only was she losing the man she fell in love with aged 17 “because he made me laugh”, and the father of her two daughters; she also felt a complete fool.

“My very being had been taken away,’’ she says. “There was no privacy, either at home or in my work. When a marriage breaks up, most people can find release in their jobs, can go into their work and it takes their mind off it. For me it was the opposite. I could sit here and take my mind off it, but going in to work I had to face it again every single day.”

Then there was the pain visited on the couple’s daughter. “Elena only stayed off one day because she had to think of her education. And she was so distressed, knowing that staff had known about the affair with her father, that pupils had known. That’s one thing I can never forgive him for, what he did to his daughter. ”

As Hillary Clinton might say, nobody knows what goes on in a marriage other than the two involved. The reluctance on the part of management and many staff members at St Mungo’s to rush to pass judgment is understandable. In addition, neither Frank McCaffery nor Claire McKeown had offended under Scottish employment laws.

“The union were very helpful, but their hands were tied by the teachers’ contract here,’’ Sonia McCaffery says. “If you’ve done nothing contractually wrong, there is nothing that can be done.’’ Frank McCaffery and Claire McKeown were merely prohibited from teaching religious education or PSE.

In voluntary aided Catholic schools in England, where the governing body is the employer, teachers usually sign up to a “morality clause”. The Catholic Education Council’s suggested wording is: “The teacher agrees to have regard to the Roman Catholic chracter of the school, and not to do anything in any way detrimental or prejudicial to the interests of the same.” Scottish schools, which have 100 per cent government funding, cannot impose such a clause.

Sonia McCaffery sits on her mushroom-coloured leather chair, in the front room of her neat, modern house. There is no trace of Frank McCaffery here now; the walls are decorated with flower fairy plates and the display shelves are full of delicate-looking but tough crystal. He is absent from the small gallery of family photographs.

Sonia McCaffery smokes menthol-tipped cigarettes in quick succession - a habit she tried to conceal during her marriage. She’s lost more than a stone in weight, and is learning to drive. She’s had letters from various men who’ve seen her picture in the paper and have declared themselves available, although most of the missives are off-puttingly sprinkled with the greengrocer’s apostrophe.

Sonia says she is happier living with just Elena than she was with her moody husband, even before she discovered the cause of what she thought was the male menopause.

She went back to school in late November. Her husband had moved in with his lover, her older daughter was away at university and she was, she says, “going insane in the house

with too much time to think. I knew I had to come back. Because by then I knew there was nothing that could be done by the authorities. It was either go back, and get my sanity back, or stay off, which would have destroyed me.”

But going back was not easy. Pupils had already demonstrated their support for her by petitioning the education authority; 50 of the 65 sixth-form pupils signed a letter expressing

their indignation. On her first day back, sixth-formers - friends of Elena’s and most of whom she had taught earlier in their school careers - gave her flowers, balloons and wine. Younger pupils pinned up a prominent welcome on her classroom door. The reaction from staff, close friends apart, was more ambiguous.

“I did get ‘It’s nice to see you back’. Some people said they thought it was absolutely horrendous what had happened. But some of the male teachers, even if they sympathise with me and Elena, still see Frank as one of the lads. Other staff felt they shouldn’t take sides, and had to be very professional.”

For around a month, the three teachers and Elena skirted unhappily round each other in school. Falkirk council’s education department took the unusual step of indicating that it would be sympathetic to any requests for voluntary transfer, while still insisting it had no justification for intervening.

Then the story broke in the local press, just before the end of term. The tabloids were all over it instantly, and Frank McCaffery found his private life laid bare over the national breakfast table. But he and his lover appeared to want to tough it out at St Mungo’s - motto, “Let Christ Shine Through You”.

On the first day of term after Christmas, however, photographers were once more camped around the front entrance, and the pressure apparently got to Claire McKeown. She left school for good around one hour later.

Sonia McCaffery still avoids the staffroom. If she passes her husband in a corridor, she turns away. She believes there should be a change in employment practice. In the world of business, large employers use their common sense and transfer employees in such situations. “It’s inhumane to expect people to work like that and pretend that everything is okay and that you can go on behaving normally,’’ says Sonia. “Whether people want to admit it or not, when something like this happens it does affect relationships and atmosphere.”

If she has used the press

to hound out her husband’s

mistress, she feels only the tiniest bit guilty. “This is sweet revenge,’’ she says, drawing deep on the menthol. “I’m only a human being.’’