- Plant a hazard, then wait.
Taking the concept of the oubliette a step further, in Charles Portis’s True Grit, outlaw Tom Chaney describes a snake pit into which he threatens to toss our heroine Mattie Ross. Then lots of other stuff happens. Eventually Mattie manages to shoot Chaney, but gets knocked backward by the recoil of her Colt.
The heart-clutching moment comes with the tumbling Mattie’s realization: “I had forgotten about the pit behind me!” The beauty is that the pit has been lurking in the back of readers’ minds all along.