Four Sport Relief volunteers immerse themselves in the lives of real people living with long-term homelessness. Comedian Nick Hancock, TV presenter Julia Bradbury, former snooker player Willie Thorne and celebrity cleaner Kim Woodburn must not only deal with the business of day-to-day survival on the streets, but the reality of people's lives unravelling in front of them. They are paired up with homeless buddies to experience the inventive and secret methods of survival used by many that are part of a homeless world most of us are totally unaware of. They discover that their new homeless friends now living on the streets were once successful professionals with families and comfortable homes, and just how painful it is to lose everything. All four volunteers also become involved in getting to the bottom of the root causes of homelessness - with some surprising results - and what possibilities there are to get off the streets. This social experiment, led by The Big Issue founder John Bird, aims to expose the realities of an increasing homeless problem in the UK. The number of rough sleepers has gone up 55 per cent and the average age of death is just 47 years old - 43 if you're a woman. Meanwhile, one in ten of us will experience homelessness in some form during our lives.