Tree surgeon Kevin, 57, arrives at King's College Hospital in London with breathing difficulties, having fallen off a ladder onto a metal bar, while 11-year-old Archie has cut his lip in an accident at school and is worried about stitches. Elsewhere, a drink-related fall has left 53-year-old John with a head injury, and barman Ross, 31, needs treatment for a fractured eye socket following an alcohol-fuelled night out