This idea was originally meant for my educational online store, Level 4, Topics Copyright & Patents.
About the value of secrets or patents.
Two friends invent something. They share this info freely, feeling like anyone should be able to make this, and secrets are unilaterally bad.
But then one of them secretly acquires a patent for it, but only for himself. (“Come on. I did most of the work. Besides, you don’t care about credit, didn’t you say?”)
Things get out of hand, and at the end one of them has turned that invention into their biggest weapon and is threatening to kill their old buddy with their own invention?