Each year in Britain, we lock up 2,000 school-age children. Vinney Green Secure Unit locks up some of the youngest and the most troubled; the kids no one else can manage - whether they are a danger to each other, or a danger to themselves. Filmed over a year, with unprecedented access to the unit, the children and the staff who care for them, this extraordinary series tells their stories and finds out what's being done to set them straight. It documents the journeys of boys and girls who are behind bars, and follows the daily life at Vinney Green as the staff try to change them.Vinney Green houses 24 children aged from 10 to 17. Some have committed very serious crimes. Others began getting into trouble when they were at primary school. Some are sent here for their own protection. And for some, simply the chaos of their lives has led them down the wrong path. For most this is their last chance - and an opportunity to change. In their own words, they explain what it's like to be locked up while you're still a child.This film follows three of the youngest boys in Vinney Green, who started getting into serious trouble when they were just nine years old. Kalem has been inside the longest and faces spending his teenage years behind bars - "I went the down the wrong way". Kieran is there for the second time, but with only a few weeks at the unit it will be hard for the staff to have any effect. Tali has just arrived, but is so volatile he's struggling to fit in - "I'm not a guy that likes people around me 24/7 - I'm a guy that likes being free so it's hard for me..." .Are they being locked up to punish them or change them? And can Vinney Green turn them around?