Conflict

Okay, we're now going to discuss the fist, and probably ONLY law (nay, commandment even!) of stories.

THOU SHALT HAVE CONFLICT.
And to show you what I mean we're going to look at the best movie of the year, X-Men First Class.
Seriously, if you've not seen it, what the hell have you be doing with your summer? Summers were meant to spent in the cinema dudes!
Level One. Physical. Surely I don't need to explain this? This is your basic black hat v. white hat. It's your jedi v. sith. No talk, no discussion or debate over the rights and wrongs, just put two men in a room and give them a gun each. Sebastian Shaw and Erik. You know they're never going to be on the same side, not never, not no how. Sorted.
Level Two. Emotional. Should you or shouldn't you? This is (typically) internal. The character is in conflict with himself. There's the option of the easy way, or the hard way. Both will get the same result, but one is usually moral the other isn't. It could be a bloke dropping his wallet on the street, thick with cash. Do you pocket it or run after him and hand it back? This is Erik's conflict throughout, knowing he's on the path of damnation but will never permit himself off it, because that requires forgiveness and that's something he doesn't have.
Level Three. Idealogical. Professor X and Magneto are great examples of friends that can never be true allies because their idealogies are too different. Prof X believes that humans and mutants can live side by side, Magneto believes they can't, one will hunt down the other. What's interesting is their backstory provides the logic of their beliefs. Magneto been a victim of the Nazis, while Prof. X can read peoples minds (this was something that should have been made more of) so he can see peoples true intentions. I like to think that's what's led him to faith in humanity. If there's one slip in this story is that Erik's backstory is so overwhelmingly powerful (as it should be) that Xavier seems naive in comparison. Xavier's convictions should have been 'bumped' up so we're wholly behind him too.
Notice how I don't mention morality as a conflict because BOTH sides should always believe they are morally right. It's never a choice between good and evil (which is never a choice), its a choice between two goods or two evils.
So, X-Men First Class. Go see it.