When you start to consider story beyond the three act structure (the basics being: beginning, middle and end) you realise that even if you map out your story you must know your character before doing so. You must also engage in the form you are writing in e.g. bloody read or watch something because you are not as gifted and talented as you think. Everyone has the scope to learn something new. Knowing your character though allows you to map their journey, give them a final racing line to cross over but you must not fall into the trap here of putting plot over character. You are creating a map and that does not replace voice, beat and honesty.