One of the sweetest old chestnuts beloved of writers is the notion that a story is driven by what a character wants. Quite so.
It's a convention, it's a construction and it's a fakery of the highest order, yet we must have it so.
In real life, people are not propelled by singular obsessions, they are in fact a mess of conflicting wants, warring desires and to-do lists. This does not make for a great story. The ruse of a story is that the heroine or hero has a one-track mind. Those of you enjoying the BBC TV series 'Gold Digger' may not have stopped to consider how likely it is that a professional man in his late thirties with a family is obsessed with his mother's new boyfriend being a tad on the young side? Sure, in real life, he'd raise an eyebrow then get back to his in-box. But then there would be no story.
An entertainment requires some stage machinery that's about as sophisticated as a canon that fires one canon ball. We entertainers pull a fast one on the...