Here's a question that has come up recently, and I don't know where in the forums to ask it.
Set up: I write and produce a play, and in it were copyrighted characters or situations. Owner of the copyrighted materials gets their knickers in a bunch over things -- as is their right -- and decide legal action is in order.
The targets of said legal action would be the writers and producers, naturally. Would they also target the actors? the stage people? Could they?
My common sense says no, but when have laws ever made sense? I would think not only because you're assuming that the cast/crew didn't know it was copyrighted material.