Know your subject is advice often given to writers. The writer should know every single detail of their characters and the world they inhabit – not just stuff that will obviously crop up in the narrative, such as childhood trauma, but the banal stuff too: what they eat at breakfast, a typical working day, bad habits, catchphrases, and so on. It may be that none of this background makes the final draft, but readers have an intuition; a sixth sense that tells them whether they are in the hands of a writer who knows their subject or not.
In Uncle Flynn, I wrote an elaborate backstory for Max’s father, much of which was revealed in the final act. But I cut the entire chapter because it took the focus away from Max and his character arc. However, the dialogue that remains contains enough hints and oblique references that allow for a certain degree of reading between the lines. This ultimately strengthens the final scenes with Max and his father a great deal, but had I not written the backstory, these undertones would not be present.
To give another example, the antagonist in Children of the Folded Valley – a novel I hope to publish in the future – has a very detailed history that informs his later decisions. However, I deliberately excluded this background because it undermined how evil he seemed in the eyes of other characters. No one would ever think they were a villain (in fiction or reality), but their actions will always appear without context to the protagonist unless they are specifically explained by the antagonist. In this case, such an explanation would have been out of character, and since the novel is a first person narrative, the villain retains his cruel core throughout. However, what this villain does has been thought through in great detail, and is based on many things, including what happened in his past. I could not have written the story without knowing this, even if this knowledge is not ultimately passed on to the reader.
In addition to characters, it is vital to know the world of one’s writing in every detail whether contemporary, historic or fantastic. Historic settings obviously require research, but the temptation with contemporary settings is to “wing it”. Personally I think this is a huge mistake. Even if a plot has a contemporary setting, knowledge of that country, city, town or village is vital. If, say, the village is made up, the general area probably won’t be, so again local knowledge is vital. Those little details add critical authenticity. Obviously one can play fast and loose with geography (I often do), but it is vital to know all that can be known about the setting – sometimes including its history even if it isn’t a historical piece.
Of course, the final product may not contain all this information. In the case of Uncle Flynn I excised a good deal of references to local villages and Dartmoor landmarks simply because most readers wouldn’t have a clue what I was referring to. But knowledge of these local places was vital when planning the story, and in many cases they were a direct inspiration for plot events.
If creating a fantasy world, a deep inner knowledge of characters, places and history is even more critically important. For instance, JK Rowling wrote a history of every single building in Diagon Alley. “Winging it” in a fantasy setting is even more dangerous, as the reader will sense the thinness of knowledge and disbelief will no longer be suspended. I have written a few fantasy books both for children and adults that have been taking shape for a number of years now. The reason they have taken so long – and the reason I am still working on them – is the sheer level of planning needed in terms of characters, family trees, histories, geography, languages, cultures, metaphysics and so on needed in the planning stages. Much of this material will never see the light of day (although for some of these books there will be supplements), but again I know if I cut corners, the novels will suffer.
The principle is also true in film. In preparing Jessica Chastain’s character for Zero Dark Thirty screenwriter Mark Boal will have written extensive character biographies. He will have shared this information with Jessica Chastain, even though none of it appears in the film. However, anyone watching the film will sense the depth of the character, even though the plot offers no distractions at all from her single-minded quest to get Bin Laden. Her character – and the film – is all the stronger for its lack of subplots, family background, love interest and so on. But I guarantee you it will all be known by Mark Boal and the director Kathryn Bigelow, and Chastain’s performance is informed by this knowledge.
One final point: I’d say a good ninety percent of story preparation is deciding what not to write, what won’t be included. Ninety percent of ideas range from mediocre to rubbish, and should be destroyed. It is worth mining through these ideas to find the gems that will form the story. On occasion, someone will read my work and say “I like your choices”. That is the ultimate compliment, because it means the person concerned understands the process of boiling a story down to its strongest, essential elements – typically six months of agony condensed into a novel that can be read in a concentrated stint of a day or two.