In a quiet corner of Cardiff, a unique driving centre transforms lives every day. Here, higher-risk drivers, who through illness or accident have been stopped from driving, have the chance to prove they're safe to be on the road. To lose the ability to drive is to lose independence, identity and sometimes livelihoods. Many drivers go to the centre with great hope of getting back behind the wheel. Others are reluctant, fearing they may be taken off the road forever. The driving assessors face huge dilemmas - they decide if people can have the freedom they desperately want but if they make the wrong decision, they could put the public at risk.

We follow the fortunes of four drivers: mum-of-four Fand who had to surrender her licence after a debilitating stroke at 38, former lorry driver Glyn who has been diagnosed with dementia, Huw who lost a leg following a life-threatening infection and 17-year-old Emily, who lives with cerebral palsy and would love to be the first among her friends to get a licence. All will undertake the ultimate driving test. Everything is at stake and each one is desperate to prove they are fit to drive.