Totally not copyright. Copyright applies to software too, but patents are the one everyone cares about. The idea of patenting plots is a good one. In fact, it m

Totally not copyright. Copyright applies to software too, but patents are the one everyone cares about. The idea of patenting plots is a good one. In fact, it might even be legal _except_ that everything that can be done in a book has been done already. Software is such a young field these immodest trolls are able to exploit them. So to clarify: Saying two different movies both of which has the "friend turns out to be bad" are copies is wrong; that's just not enough of a similarity to base a copyright case on. However, if you happen to find a way to patent it (which you probably could if there hasn't been prior art), you would be able to sue for patent infringement.