Jon Snow: After half a century, a forgotten scourge is back

The housing charity Shelter estimates that there is a shortage of a million homes in the UK

He was the bogeyman on my childhood; his name was synonymous with exploitation and cruelty meted out against the most vulnerable in our society. What he did in the 1950s and early 1960s entered the Oxford English dictionary as Rachmanism. In short Peter Rachman bought up swathes of slum housing in West London, forcing out the long-term white tenants within, and replacing them with high-density new Afro-Caribbean immigrants.

Rachman is back. The man may have died in 1962 but the housing abuse that he pioneered is returning. The Rent Act of 1965, the myriad laws and regulations that were drafted to protect private rental tenants, have failed.

We had not the slightest difficulty in finding today's Rachmans. After choosing an area in the north-western part of Manchester, we found three rogue landlords with empires of housing that numbered in the hundreds.

One of them, the Meridian Foundation, even operates as a charity to provide low rent, no-deposit homes for poor people. Visiting some of its properties, one finds Hazel and her three children in a house in which you would not leave a dog for a night. I could not enter by the front door; it had been nailed up with plywood after a break-in months ago. When I got in through the back, the stench of fungi and other growths was overwhelming. The sleeping 16-year-old's face was no more than a foot from creeping black and grey fungi. No wonder her asthma is so bad.

I met Mr and Mrs Halstead in the home in which they had lived for 42 years, which had been bought from beneath their feet in return for a pledge that they could stay on at a low rent for the rest of their lives. Four years on, they were forced out by the very rent hike they were promised they would never suffer.

We even found large numbers of illegal immigrant workers housed in their hundreds in garden sheds in an area west of London.

It perplexes me that society can be so consumed with the state of education and health provision in Britain, and yet turn so active a blind eye to the true state of where people actually live.

The housing charity Shelter estimates that there is a shortage of a million homes in the UK. Britain today has a housing crisis on a level with that at the end of the Second World War but is building fewer homes than at any time since the First World War.

We were told by a number of housing officers that local authorities dare not inspect many establishments for fear that they will have to re-house those inside.

Dispatches: Landlords from Hell, Channel 4, tonight at 8pm.