Maths teacher, Mr MacGregor (Patrick Troughton) is distraught when his daughter, Jenny fails to achieve the academic success of her older brother, a successful young man and clearly the apple of his father's eye. He accuses his wife (Judy Parfitt) of infidelity, claiming that no child of his could fail to make the grade. and goes off into the night to meet his son. Left alone Mrs MacGregor confides in Ian Craig's wife, revealing that Jenny is indeed her father's daughter but that her son was the result of an affair early in their marriage. Jenny, who has overheard the bitter arguement between her parents cries alone upstairs in her room .The title of this episode - A Wise Father- is ironic as he does not know his own child. However the truth is revealed when her father returns and Jenny (Sheila Arthur) appears at the top of the stairs and is finally embraced by both parents.