I was really pleased with this one.  Sometimes I think I am at my best when I use a “reveal” type of punchline…  where the reader is not supposed to know what is going on until the final panel.  Some crucial detail is revealed which throws the whole thing into a new and (hopefully) funny light.  Then you go back and read it again in context.

That might sound like an easy way to write a gag, but it’s one of the toughest I’ve tried.  People are very hard to surprise, and with a reveal, you’re hanging everything on the successful attempt to catch them off-guard.  If the joke pancakes, it’s going to hit hard.