So, it's a standard story in sci-fi

[conuly]

The intrepid hero(es) wander off and do something that gets them "out of phase" with the rest of the universe. They can see and hear everybody, but nobody else can see or hear them. Maybe they're totally incorporeal, and maybe they can move things around.

But why doesn't it ever work the other way? Everybody else can see and hear them, but they're wandering around in a fog, only able to see the other things and/or people out of phase?

Comments

[conuly]

Maybe not all the air in the universe is in the same phase as the air we now breathe, and our intrepid heroes are breathing the out of phase air.