You know the law, the one that says (approximately) if you introduce a gun in the first act then it has to go off by the third. Get rid of it. Now!
There are big problems with it:
1. It is enforced through knee-jerk reaction. Specifically, if a gun shows up in a play reading, someone will inevitably make a comment about Chekov’s law, as if Pavlov’s dog were enforcing it. It inevitably comes up if there is specifically a gun, even though what I’ve read about the law indicates it was being used metaphorically (although if so, it does seem to be his favorite metaphor).
2. If it is universally followed, then there will never be any suspense as to whether the gun will go off, only as to when, as to who will fire it, and as to what damage will be done. But there ought to be suspense as to whether it even poses a danger.
3. Actually there are counterexamples to Chekov’s law, the red herring and the MacGuffin. So why can’t a gun be one of those? But if you try this, you’ll likely get grousing from someone about having broken Chekov’s law.
4. And a playwright friend and colleague points out, its presence can simply be part of setting the stage. As he puts it, “Sometimes a gun is only a gun.”
Actually, I’m tempted to write a play in which a gun is introduced in the first act, and is used in the second act (the third act mostly having long since disappeared) to hammer nails, break open a rusty hinge, smash dishes, anything but fire at someone.
Nawwwwwwwww. Too much trouble.