Moving forward

I have figured out what my film is about. The only problem is, I have no idea what my story is.

Perhaps I should clarify.

My film is based upon the statement, "Any form of idealism, once rejected by the idealist, leads to nihilism." My film is going to trace the lives of an idealist as he confronts the collapse of his idealistic structure and becomes a nihilist, a nihilist as she flounders in a cycle of meaninglessness, and another nihilist who breaks out of the cycle and becomes an existentialist.

This is all well and good (at least in my mind), except I have no idea what actually is going to happen in the film. I want to include a catastrophic event that links the lives of the three characters (like the car crash in Amores Perros), but I'm having trouble creating a life-altering event that can be produced with next to no budget.

I'm further confronted (again) with the issue of time. An idealist does not shed his ideals over night. He only surrenders after a long war of attrition that ultimately leaves him defeated. How to express this in ten minutes currently escapes me.

As for the episodes of the two nihilists....I haven't even begun to try tackling those yet.