Back to looking at storytelling techniques again. This time, an example of "mystification" from the excellent "Zits" by Jim Borgman and Jerry Scott.
I call this technique "mystification", because it presents the reader with a riddle, a mystification, and the gag is the explanation in the final panel for this apparently inexplicable behavior or situation.
In this case, Jeremy returns home – in panel #1, we see him slamming the door of his car, giving us the valuable information that he has just arrived wherever he has just arrived. In panel #2, we see his mother sitting on the chimney, which informs us that he has apparently arrived home. We also see them exchanging normal son-mother greetings – "Hi mom.", "Hello Jeremy" – so apparently Jeremy's mom sitting on the chimney isn't particularly weird to either of them. Why on Earth is that so?
We have our mystification, and in the final panel, we get the answer: Jeremy's friend Pierce is visiting, and he can't find his snake. He has even, as he tells Jeremy, asked Jeremy's mother if she's seen it.
Now we see why the strip had to have that initial panel of Jeremy arriving home. It was necessary to have Jeremy just arriving to the house, otherwise he would have known that Pierce hadn't found his snake yet. And it was necessary for him to ask Pierce about that, because that is what prompted Pierce to divulge that he had asked Jeremy's mother – which is what resolved the mystification for the reader!
Borgman and Scott well and truly know their craft. I doff my hat in their general direction.