Having run an art gallery in London with my wife and having met many art dealers, I can admit that there is an element of autobiography in the story called A Chancy Business in Where Reason Dreams. All art dealing is a bit ‘chancy’ – will the picture you have spotted at auction be recognised by other dealers, will you have luck finding a picture in an antique shop, will there be serious buyers at your private view, have you discovered a long lost masterpiece? The element of luck in art dealing is far greater than in other areas of retail and most dealers I know relish this element of chance.

Things can go wrong. Sales can slump, areas that interest you can quickly go out of fashion and your stock of art works can fall in value, interest rates can rise without warning leaving your borrowings exposed. These were some of the problems that Rupert was facing and he was fast running out of money. The temptation to steal the Pissarro was simply too great, but he never intended to kill Mrs Ridge.

Rupert almost got away with his plan but for the sharp eyes of Professor Rheinhart at the Barnes Foundation in Philadelphia widely acknowledged as the world authority on Camille Pissarro. Rupert’s charmed life came to an abrupt end.

You can buy When Reason Dreams from independent bookshops , Winstone’s, and Amazon.