I'm at the coast, looking at how high the surf is. I show somebody, or they show me - you can't even see the edge, because it's up over this hill. We go up just over the hill, a long ridge of sand or small rocks, to see how high the tide is, and how big the waves are. They're not huge, but it looks like an angry surf.

Suddenly I'm about 20 feet out in the surf, with the waves up to my waist. I think no big deal; my clothes are wet, no problem. Oops my wallet is probably wet, that's a bummer. Then I can't move, the tide is pulling me out. I can hold my position, just barely, but I can't go back up onto the shore.