Strangely paced/structured (spoilers)
I'm trying to think if I've ever seen a movie with this kind of time structure. We spend the first fifteen minutes briskly moving through several locations during Saturday daytime (including the mother/cousin/aunt subplot).
Then a dissolve to the ballroom, and roughly the next hour is spent on the two principals' "meet cute" and subsequent "date". (The only other character study or romance movies I've seen that spent that much time on one evening finished the entire film that night, or at least before anyone went to sleep.)
We get another fifteen minutes working like a bookend to the beginning, quickly moving through the whole day on Sunday (except for slowing down briefly to introduce an eccentric ancillary character with a fondness for Mickey Spillane) and resolving the aforementioned family subplot.
Then the complication/impediment to the couple's happy ending, a standard romance trope, is introduced with five minutes remaining in the film, and resolved literally within the last minute! Meanwhile, Clara has no lines on Sunday, and only is seen very briefly just before the end, crying as she watches TV with her parents.
It's not a bad thing, necessarily, to be unique structurally. But the thing is, I sympathize with their spending a lot of time on that middle section of Marty and Clara meeting and spending time together. They have a lot of chemistry (even if Clara's looks don't fit all the insults in the script), and this is the most enjoyable portion of the film. So why not include a little more Marty and Clara together in the concluding portion of the film? It's only a ninety minute movie, so it's not like they had no room for another few minutes of running time. It comes across like "whoops, we're out of time, let's scramble to wrap this up". (The movie has a 100% at Rotten Tomatoes, but the NY Times review does include this caveat: "Except for a rather sudden ending that leaves a couple of threads untied and the emotional climax not quite played out, it is a trim and rewarding show.")
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