What leaped out to me is that it’s very clever filmmaking, not just telling a good story, but how it told it -- replaying scenes from different perspectives and jumping around in time on occasion. But you don't lose track of the structure, it's very clear and most of the time follows a straight path. The jumps keep it offbeat enough to keep feeling fresh.
As for the story, what I liked so much is that there’s plenty of conflict, as the lives of the two leads -- a record exec and songwriter girlfriend of a rock star about to break through -- fall apart, but it all happens naturally, and is faced in a believable, adult way, not forced or awkwardly. A scene where she slams him for being lazy in letting his life get away from him doesn't turn into a Movie Moment, but actually leads to a wonderful scene where things aren't as they appear on the surface, and ends up drawing their relationship closer. And is that relationship work, friends or romantic? The film takes it time believably building its path to get there.
As the two, and their extended circle -- very extended (and one of the treats is how it gets that way) -- rush around the city, grabbing any locales to record their by-the-seat-of-their-pants album, a seemingly ordingary scene in an alleyway builds lovingly. But even better is a gorilla recording session on the rooftop of skyscraper that turns into just joyous filmmmaking.
Oddly, when I went, I had forgotten that it was the same filmmaker as Once But five minutes in, I felt similarities in tone and thought, “Gee, I wonder if they’ll try to make this a stage musical like they did with that Once.” Particularly since this has a LOT more music -- and all the music quite good.
But then, all the cast is good, most intriguingly even those who aren't trained actors. Adam Levine does a particularly good, easy-going job. He doesn't get deep under the character, but makes him real and believable, and not the cliche a weaker performance could have turned it into. Yasiin Bey (Moss Def) is terrific as a record executive, and CeeLo Green, though a little rough on the edges, is great fun and does fine. Then, you round out the cast with Catherine Keener, Hailee Steinfeld -- and happiest of all (for me) one of my faves, James Corden (from The History Boys, the star of last year's One Chance, and Tony winner as Best Actor in One Man, Two Guvnors). It's in a small role for him, but he’s a pleasure, as always.
It's a small film, but rich, funny, charming, thoughtful, and very musical, and keeps going in slightly different directions than you think. Here's the trailer. The movie is much more, but this does a reasonable job --