To come alive on the page, your hero and heroine must be more than two-dimensional cardboard cut-outs that you move around the stage. You should not be asking yourself “what can I make them do next”. If your characters are blood-and-bones, heart-and-soul real, you will know what they would do, just as you instinctively know what someone close to you would do in any given circumstance.
You may hear authors talking about characters who “take over” the story. That is not because the author is not in control of her characters, but because she has created three-dimensional, living, breathing people, men and women she knows so well that her writing brain is flying ahead of her fingers on the keyboard.
To truly know your characters you must understand not just what they look like, where they went to school, what they do for a living but see them living in their own world, having a life before you write Chapter One.
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