"Betty Boop, M.D." finds our heroine selling patent medicine along with her friends Bimbo and Ko Ko. While you can see that they are only filling the bottles with water, again and again, frighteningly unpredictable changes take place in anyone who drinks it--and after Betty does her dance, everyone seems anxious to have it.
There really isn't much plot in this one. Betty sells fraudulent 'medicine', sings a song and the film then shows all the weird reactions that happen to those who take it. The song is rather zippy and enjoyable but it seems very, very weird to have a beloved cartoon character behaving in such an amoral fashion. This is really awfully strange and vaguely unsatisfying. The only real plus is the Fleischer Brothers Studio animation--which was much better than most of their competition.