If you have an adventure story to tell, you must never let your scenery get out of hand. The more unusual your characters and their doings, the more recognizable must be the world through which they move. The soul may be strange, the motives unlikely, but the clothes and the furniture must conform to daily living…. [Robert Louis] Stevenson, John Buchan, Francis Iles—in short, writers of great or good adventure or detective fiction—have in almost all their books obeyed [this rule]. Let it be said for Mr. Shute that he obeys it too.

"Pied Piper" is a most improbable tale, in a quite probable setting. An old Englishman, Mr. Howard, is trapped in France by the German invasion of 1940. He agrees to escort two little English children back to England, their parents having decided to stay in Geneva….

It is an old and honorable tradition that...