Mickey's Gala Premiere is one of those animated shorts that is probably more interesting as an artifact of Hollywood history than it is as a cartoon. The whole plot of the short revolves around a premiere of the latest Mickey Mouse cartoon. Apparently Mickey's premiere is the social event of the season, since a virtual who's-who of the film stars of the day turn out to watch the antics of everyone's favorite corporate mascot (even Will Hays himself makes an appearance!). Old movie junkies will probably enjoy this one quite a lot, as it offers a great opportunity to spot their favorite stars in cartoon form.
Personally, I like this cartoon because it's probably the only time that Joan Crawford and Eddie Cantor ever appeared in a film together. Now there's a pairing I'd like to see. They're even sitting next to each other in the audience, for Pete's sake.
By the way, if someone could tell me who the fellow taking tickets about two minutes into the cartoon, I'd greatly appreciate it. I've seen him caricatured in many classic cartoons, but I have no idea who he's supposed to be.