Being the nerd that I am, I can't help but nitpick here - this was not Batman's first case. It was his first APPEARANCE in actual comics, yes, but he had cases before that. For one thing, in the first panel of this story where idle pipe-smoking Bruce is talking to Commissioner Gordon, Gordon mentions how "this fellow they call the "Bat-Man" puzzles me!" That would seem to be a pretty clear implication that Batman has had at least one or two other cases already. Also, I'm pretty sure there was a later Sprang-era story talking about 'Batman's first case'.