Actually something like this did happen to me. Several years ago, I was doing my "Route 66" thing and travelling around the country. Anyway, late one evening I found myself near Ashland Ohio. I noticed a drive-in movie so I pulled around the outside fence with the idea of watching the movie and then sleeping in my van. Well, while watching the movie I began changing clothes in preparation for sleeping in the back of the van. Suddenly the call of nature hit and I thought it would be kewl to go out in the nearby bushes and make use of the leaves. So out into the bushes I walked, completely Au Naturel except for my slippers. I did my thing and walked back to my van to discover that I LOCKED MYSELF OUT!!!
So there I was buck nekkid and locked out of my van. What to do? I couldn't very well walk down the road seeking help. For long agonizing minutes that nightmare of being nekkid in public really hit home, although as yet no one had seen me.
Fortunately I finally remembered that a couple of years earlier I taped a key with duct tape to the van's frame underneath. I found the tape which basically welded itself to the frame and desperately clawed away at it with my short fingernails (not an easy task) while praying the key was still there. Luckily it was and I was able to get back into the van and into my clothes.
Anyway, the reality of being nekkid in public (although my public hadn't yet seen me) really does feel as sordid as that nightmare. Hopefully it is an exerience that WON'T be repeated.