Blessed with an A-plus creative pedigree that includes the director of "Hamilton," writer of "Tick, Tick ... Boom!" and songwriters behind "Frozen," "Up Here" joins the growing list of musical series, in what amounts to a young-adult version of "Inside Out." The show, however, isn't as good as its auspices, and the music can't mask the thinness of the story, translating into a pretty flat episodic rom-com, just with a better-than-average beat.