Instead, the mother of four had taken her sons, aged from 7 to 13, to a women's refuge, where she was greeted by a group of women who had helped her to plan her escape. No one took much notice of the boys on that first evening, but by the end of a six-month stay their presence had become a constant source of aggravation.
In the meantime, Paul Evans tried in vain to get his sons back. He issued two warrants through his solicitor - one for his wife's arrest and the other for the return of his children, but the High Court decided that it was in the children's best interests to remain with their mother.
From then on the relationship between mother and sons deteriorated rapidly, with the children becoming rude and out of control. They would continually phone their father, begging him to rescue them, only to be told that, much as he loved them, there was nothing he could legally do to help. When their mother moved from the refuge into a flat and they were able to visit their father regularly, they begged to be allowed to stay with him.
In the end they started running home to him - at first two or three times a week, then two or three times a day - until finally, following several more court hearings, it was decided that Paul Evans should, after all, be given care and control of his four sons. One point in his favour was that several years previously he had given up his job to become a house-husband so that his wife could carry on her professsional career.
Paul Evans is a softly spoken, gentle man who seems visibly shrunken by what has happened. His wife's departure clearly came as a bolt from the blue. 'I always thought of my marriage as a working marriage,' he says. 'It had its ups and downs like everyone else's but right up until the time my wife left me, I was under the impression that we were trying to resolve our differences.'
Carolyn Evans, according to her husband, would fly into a rage without warning, usually directed towards the children. Over the years, her husband had established methods to distract her, but her sons had no such tactics and were the ones who suffered most. It was worse when their father was out, the children said, and often he would return to find them out of control with grief.
The children feel that throughout countless court hearings judges, social workers and, most importantly, the Official Solicitor - who represents them - have been biased in favour of their mother, and it was only the boys' refusal to stay with her that eventually gave the courts no option but to grant Paul Evans custody.
Since then the court has ruled that enforced visits with the mother must be maintained, despite the fact that every attempt at reconciliation has so far failed. At the root of their father's discontent is the belief that contact with the mother is seen by the legal profession as sacrosanct, whereas contact with the father is seen as expendable.
Last year, in a letter to the Lord Chancellor, Lord Mackay, 13-year-old James Evans described the misery the brothers endured during their time at the women's refuge.
All four boys clamour to speak at once, listing a catalogue of abuse, which is accompanied by a great deal of table- thumping and garrulous behaviour. 'Their way of dealing with all this is to make it into a big adventure,' says their father, 'but the whole thing has traumatised them.'
On the face of it they seem lively, well adjusted boys. Only their strong dislike of their mother is disquieting. According to Charlie Lewis, senior lecturer in child psychology at Lancaster University, the overriding reason for a child's vehement opposition to one parent is normally fear.
'If the hostility these boys feel towards their mother is sometimes hard to understand, perhaps it is because we are used to hearing of parents who, despite deplorable acts of violence, still win their child's loyalty and affection. It is different, however, when a child has a history of stability with one parent, because that creates an environment in which the child feels safe to say what he or she really feels. Losing one parental relationship therefore doesn't matter so much if a child feels sufficiently comforted by the other relationship.'
James, the eldest, seems the most disturbed. His earliest childhood memories are of a mother who loved him, and he cannot understand what went wrong. Eleven-year old Steven is less distressed, perhaps because he has never enjoyed a good relationship with his mother. His father describes him as a 'free spirit' and the inspiration behind the children's fight for justice.
The two youngest, Alex and Luke, are less coherent. They have become unnaturally clinging and are frightened to leave their father for any length of time, frequently regressing into childish behaviour. They think that if they act like babies then everything will be the same as it was before.
It is nearly two years since the boys were reunited with their father in his cramped council flat. The place is cluttered but homely, with the washing machine and tumble dryer permanently on the go. The boys seem happy enough, despite the fact that their mother has threatened to have them put into a foster home. If you ask the children why she should want to do this, the answer is simple: 'She doesn't like us and she doesn't like Dad even more.'
On several occasions their mother has tried to make individual applications to the High Court to have her sons put into care. These applications, however, have so far been turned down on the grounds that the boys still have a father who is willing and able to look after them.
Asked what they want most in the world, all the children have the same resolute answer - 'to get rid of Mum and stay with Dad'. Visits to their mother have been an ordeal. 'She doesn't care at all,' says Steven. 'We go there and she won't talk to us. At the weekend she refuses to go out because she's always waiting for an important phone call which never comes, and if we do the slightest thing wrong she lays into us.'
If the boys seem unrepentant in their attitude towards their mother, it is mainly out of an urgent and instinctive desire to protect their father, although sometime Paul Evans wishes it were otherwise. He knows that if the children could forge a good relationship with his ex-wife, it would enhance his position as the custodial parent. Consequently he does everything he can to encourage visits.
He is staggered, though, by the initiative the boys have shown. He helped them compose letters to solicitors and agencies but the ideas came from them. 'I would never have thought of all those people to write to,' he admits.
The boys are sharply aware of society's reluctance to put the blame with the mother. 'If our father had so much as laid a finger on us he would be in prison by now,' says James, 'but our mother can get away with it.'
A senior police officer (who did not want to be named) said that there was some truth in this. 'If a woman bruises a child, we have to accept it because society accepts it. I don't like leaving children in the care of violent women but often we have to, otherwise society cries out against us.'
Since they returned to their father, the children have tried through the courts to have the Official Solicitor dismissed from their case, claiming that he has never represented their needs. 'The Official Solicitor has never helped us in any way,' says James. 'He didn't stop us getting hurt. He never came to see us when we needed him; he didn't make the social workers help us, or the police.'
So far, the response from the Lord Chancellor's office has been positive in its acknowledgment of the boys' plight. But father and sons alike are appalled by the hypocrisy of agencies associated with children's rights, believing that there is a wall of resentment against children who complain of being battered by their mothers.
The police, the social services, a child psychiatrist, teachers, counsellors and even the NSPCC were contacted, but failed to offer help or advice. Also, while they were at the refuge, the boys wrote to the Sun and the Daily Mirror but got no replies, and when they phoned Esther Rantzen's Childline they were referred back to the police. The boys' main desire now is to dismiss the Official Solicitor and represent themselves. 'Then,' says James, 'we could at least start naming the people who have hurt us and we might start being believed.'
This may become a reality, since earlier this year the boys heard that they had been granted legal aid to get representation in court to remove the Official Solicitor from their case. Should they succeed in sacking the Official Solicitor the four Evans boys will have made legal history.
All the names in this article have been changed.