In London, fitness trainer Dusan is in critical condition after being hit by a bus. With potential head, chest and abdominal injuries causing major internal bleeding, the air ambulance team anaesthetise him at the scene. In hospital, Dusan is declared a code red and receives immediate blood transfusions. After chest drains are inserted to help him breath, he is sent for emergency surgery to treat the source of his internal bleeding.In Gloucestershire, George is involved in a serious horse riding accident which leaves him unable to move. Worried that he may have damaged his spinal cord and his breathing may deteriorate, doctors transfer him to a major trauma centre for detailed scans.In St Albans, tree surgeon Seb falls from a high ladder onto his back whilst pruning trees. Doctors and paramedics suspect he may be bleeding internally and have internal fractures. Scans reveal several crushed vertebrae and Seb is taken to theatre for spinal surgery.