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.In the third and final film, three boys are facing the prospect of beginning their adult life behind bars if they can't change during their time at Vinney Green. This film follows them as they prepare to leave.17-year-old Ryan started getting into trouble when he was nine and still struggles to contain his anger: 'I don't lose control, I just choose to get angry'.15-year-old Ryan can't say no to his friends: 'We think we're bad - but we know the truth - we're not bad'.And Ashley, who has been in and out of secure units, needs to break the cycle before it is too late: 'By Christmas I'll be back inside - it's my life - trouble'.Will the unit have any effect on such persistent troublemakers? And will they be able to leave here and never come back?