Woody Allen is a director I respect more than I outright admire or like. He's got a unique sense of humor, a good eye for direction and a habit of telling his stories in interesting ways. He's hampered, however, by a tendency to have his scripts be overly talkative, his occasional breaks of the 'show don't tell' rule and by his habit of treating his lead characters as personal avatars (which is exemplified whenever he decides to play one). And while this can lead his movies to occasionally annoy or exasperate me, it doesn't stop them from being good or even great, as is the case with Midnight in Paris.
The plot is concerned with Owen Wilson as Woody Allen (I'm sure the character was named something else, but shut up) who is visiting Paris with his mismatched fiancee and her conservative parents and come back, I know you can plot the entire movie out from that description, but there's more to it, I promise. I can't tell you what, because it's a spoiler, but this movie does do something interesting with the formula.
Apart from telling you that the story does indeed take a unique turn at about the 20 minute mark, there's not much I can say. The direction is fine, nothing on Manhattan or even Annie Hall but fine. The screenplay is where it really shines, balancing well written versions of already well known people (trust me on that) with an interesting story and a fairly intellectual subtext about the dangers of nostalgia (something I appreciate) and some great dialogue. All the acting is great, particularly Owen Wilson giving the best performance of his career to date and Marion Cotillard (IE, the wife from Inception). There's really not a lot to say about it beyond 'it's really good.' A worthy Oscar nominee if ever I saw one, so you really should see it before the ceremony.
Elessar is a 22 year old Alaskan born cinephile and his local art theater was passing out cheat sheets for all the historical references in this movie when it was showing. And that just speaks for itself.