Martin deals with the case of a young girl who has been acting out. When Louisa Glasson mentions Ritalin to the mother, Martin tries to point out that she is not qualified to give that kind of advice. A new police constable, Joe Penhale, arrives in Portwenn but seems to have a peculiar medical condition. Martin's aunt Joan has a car accident and Louisa faints while teaching a class. Pauline is bored with being a receptionist and desperately wants to give out medical advice so Martin has a proposal for her.