Preliminary research suggests that, perhaps unbelievably, there is no existing book that discusses famous fictional detectives from the perspective of philosophical logic! This indicates one of two things: a.) There is a good opportunity here to write an undergraduate/popular philosophy book which will appeal to those with an interest in philosophy, literature and crime or b.) No-one has bothered with this because it’s a complete no-brainer.
Places checked: British Library, Amazon, Philosopher’s Index, Sloman Library.