Fear to Tread

Fear to Tread is a mystery–crime thriller by the British mystery writer Michael Gilbert, first published in 1953 by Hodder & Stoughton in England and by Harper & Row in the United States. Set mostly in London, it was his seventh novel in six years and built upon the favorable reputation he had achieved earlier with the well-received Smallbone Deceased and Death Has Deep Roots. Its main character is Wilfred Wetherall, a middle-aged, mild-mannered headmaster of "an understaffed, overpopulated secondary school for boys in the south-east of London." To further emphasize the apparently unheroic nature of the protagonist, throughout the book the third-person, omniscient narrator refers to him as "Mr. Wetherall".

His heroes fight without hope of reward, because they hate bullying; they honor, albeit with regret, the slow processes of democracy and law; they are loyal to those who have fought at their side, and they do not think trust a mug's game. In short, his characters embody the virtues of the class-ridden but romantic public school tradition.

http://www.nytimes.com/1982/09/12/books/who-did-it-michael-gilbert-and-p-d-james.html?pagewanted=2