Doctors at Balham Park Surgery are faced with a series of surprises, including the victim of a road traffic accident who staggers into the surgery intent on getting a doctor's letter for his solicitor. Meanwhile, Dr Heather Watson treats a man who has been bitten by a mysterious insect while camping, before finding out that her patient is experiencing agonising pain from his bowel movements. Plus, a routine ear examination takes an unexpected turn when Dr Chris Pearce's young patient reveals she has noticed blood in her stools