Today 600 people will wake up, get dressed, perhaps kiss their loved ones – and then vanish. They are among the 210,000 people reported missing each year, and in some cases they never see their families again.

There are many complex reasons behind sudden disappearances – relationship breakdown, financial problems, depression – but the result for those left behind is the same: a limboish, half-life of simultaneous dread, anguish and hope.

The brutal statistic for the families left behind is that two thirds of adults who vanish do so deliberately: they do not want to be found. A study, Lost from View, conducted by York University and Missing People (formerly the National Missing Persons Helpline), found that of all missing people who are traced alive, only 20 per cent return home for good and 40 per cent refuse to renew contact of any kind. Some, usually men, go to the extreme of staging a “pseudocide” – faking death to start afresh with a new identity, a phenomenon that has come to be known with misplaced jocularity as “doing a Reggie Perrin”.

The suffering of those who disappear because of mental breakdown, amnesia or family violence should not be underestimated. But some experts believe that as modern technology becomes more intrusive, as more marriages break down and debts mount, the basic human impulse to escape is growing. These people do not necessarily want to drop out of society. As Ronald Bracey, a clinical psychologist, says: “Sometimes people feel that the life they have set for them is the wrong one, that they are living the wrong script” – people such as Alistair Liddle, a married Scottish solicitor who embezzled £18,000 while suffering stress. He contemplated suicide but decided on a new life instead, fled to Cornwall and worked as a fruit picker. Years later he was found 8st lighter, with a new partner and baby.

Frank Ahearn, a US privacy consultant, helps people who want to start a new life. He does not help them to fake their deaths or escape justice or tax: his work is perfectly legal. But he ensures that they cannot easily be traced by, say, unwanted family members and former colleagues. The number of clients, mostly men, seeking his services has increased tenfold in five years. In America he believes that the Patriot Act and a general creeping sense that the Big Brother state is watching have helped to fuel the desire to dip beneath the radar. “It is definitely more of a male issue,” he says. “Men have more of an ability to detach themselves. They might reach a point where they want to dispense with the life they have, just pick up and go.”

The internet and mobile phones, Ahearn says, have made this infinitely more possible. It is simple to run a business from a website with no bricks and mortar address. What is becoming increasingly attractive to potential runaways, he says, is the idea of a virtual life.

“You can have a pay-as-you-go cellphone, a prepaid credit card. You can have a virtual life. Ten years ago if you had wanted to disappear you would have needed a new identity. Now you don’t. The tools of the internet enable you to live and work without being found.” Ahearn’s clients have included a corporate whistle-blower and a lawyer who was being stalked by a former client. He advises people to start planning six months in advance. “Do not use your home, work or cellphone, and do not use your calling card. Do not use any of your credit cards to purchase anything in the place you are going to escape to,” he says.

The psychologist Dorothy Rowe says that it is an enduring human fantasy to disappear and start again somewhere else, and the person who loses their memory is a plot that has been used repeatedly in fiction. Indeed, each time there is a disaster such as the 9/11 terrorist attacks or the Asian tsunami some people will seize upon the opportunity to cast off their old life by letting the world think they are dead.

Rowe says that men (who are twice as likely to disappear as women) often cannot cope with a loss of face at work. “When we have that experience where we discover that there is a serious discrepancy between what we thought our lives were and what they actually are, is when we fall apart,” she says.

Ronald Bracey says stress can sometimes cause people to go into disassociative states, such as when students go temporarily blind before an exam. But he says it is highly unusual for people to lose their memories for years at a time. People either want to be missing or they are mentally ill, severely traumatised or suffering from a head injury.

Professor Nina Biehal, from York University, says her research has shown that the shorter the length of time that someone is missing, the greater the chance that they will return home. After two years’ absence the likelihood of their returning is negligible.

But those who plan their escapes should spare a thought for the torture that the families of missing people endure. I have sat in the homes of many wives whose faces are etched with the perpetual purgatory of not knowing. Bureaucracy has little mercy for those left behind. It is usually seven years before a missing person can be declared dead, and until then their family, already suffering hardship from the loss of income, cannot touch savings accounts or insurance policies. If a house is registered in both the wife and husband’s name, she cannot sell it.

But the fact is that adults have the right to go missing if they choose. A few of those who are found even refuse to allow their relatives to know they have been found. The strength of such feeling is probably summed up by a missing university lecturer traced by Missing People who told the charity: “How dare you look for me?” He threatened to sue.

www.missingpeople.org.uk

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