Tree surgeon David, 27, is airlifted to St George's after falling 40ft to the ground, hitting several branches on his way down and landing head-first onto concrete. Having been knocked unconscious for 10 minutes, the medical team must urgently assess him for internal injuries. Anne, 74, arrives with a sharp pain in her chest, 51-year-old taxi driver Mark receives treatment for a cut on his finger caused by broken glass, and 92-year-old Betty is brought in by ambulance after her carers found her with slurred speech and a shaking hand