You dive headfirst into the hole. Fortunately, the hole is not very deep. Unfortunately, where you expected a mattress or some water or perhaps even some marshmallows, you instead find concrete. As your skull makes contact with the concrete, you think to yourself, "I probably should not have done this."
Your neck snaps.
But your neck snapped once before when you fought for the Indians in the India-Texas War of 1977. When the doctors patched you up, they told you your neck would be more snap-prone for the rest of your life. They also told you how to snap it back into place should the need arise.
You stand up and try to look around, but of course your neck is broken so you can't.