Urban free climbers are a new breed of daredevils, young men and women who illegally climb cranes and buildings without any safety equipment, then hang from them, hundreds of metres above the ground, one slip from certain death... Free climbing originated in Eastern Europe, but has recently spread to Britain. James Kingston is a 23-year-old who lives with his mother near Southampton. In his spare time James scales the local 100m cranes and 200m radio towers. Now James embarks on a journey to the spiritual home of urban free climbing, Ukraine, where he teams up with the infamous Mustang Wanted, the craziest climber of them all. As Mustang and James explore Kiev, the pair push themselves to new extremes, climbing derelict buildings and tightrope-walking hundreds of metres above the city, before finally heading to the iconic Moscow bridge to attempt Mustang's latest death defying stunt. Don't Look Down is fascinating, revealing and nerve-wracking.

• Documentary