They Knew Mr Knight By Dorothy Whipple.

This is a novel by Whipple which covers some of her favourite themes. There are 2 families who have little in common, and they become involved. Then the father of one family reveals himself to be a fraudster. Thomas Blake lives with his wife Celia and their 3 children, in a provincial town, where he manages an engineering works. He is a skilled engineer but his father, who owned the business before him, was not a successful businessman and he lost money and had to sell the business to his partner. Thomas was kept on as manager but his salary is moderate and he is worried about money. He also feels that he has been let down, by the fact that he no longer owns the family business. Celia is happy enough with being a housewife with a small house and only one servant. They have 2 daughters, Freda, who is rather vain, and Ruth who wants to be a writer... and a son Douglas who is interested in science. Thomas wants Douglas to become an engineer and succeed him as manager, at least but he knows its very unlikely that he will have the money to buy back the firm. Mr Knight is from the town, and he has gone up in the world to own several businesses and lead a gay social life. He has recently bought a house near the town, Field End. One morning, Thomas is on his way to work by train when he sees Mr Knight also catching a train. Mr Knight slips and almost falls badly and Thomas manages to rescue him. Knight thanks him and they fall into conversation on their train journey. He tells Knight about his work and the problems he has, and on an impulse, Mr Knight offers to help him. He suggests a plan for Thomas to borrow enough money with his backing, to buy out the man who owns the works.