One of them is going to puke right on Superman, you can count on it.
The final story in Superman 59 (July/Aug. 49), has Schwartz, Boring and Kaye make Superman the subject of amnesia – everyone else’s!
Superman is shocked to find that suddenly, nobody knows who he is. The police treat him as if he is crazy, and Perry and Lois have no idea who he is either. All mention of him has vanished from back issues of the Planet, although Clark Kent is still known by all.
Mr. Mxyztplk is revealed as the one behind this, taking pleasure at the trouble Superman is having, making people remember him.
In this story, Superman has to solve the situation before Mxyztplk leaves for his home dimension – otherwise the spell will stay intact. That’s quite different from later stories, in which the effects of Mxyztplk’s magic vanish when he does. It also makes the resolution far more difficult, as he has to both trick the imp into saying his name backwards, but also make him want to remove the spell.
Although I am not certain of this yet, it would not surprise me if this was the last story to separate his return from the end of his magic effects. I’ll keep an eye out for that.