You don't have to have seen too many bad family-oriented comedies to figure out what one of the big setpiece moments in RV will be, given that it stars Robin Williams as a white-collar dad taking his family on a trip in a huge mobile home, with which he has no experience. Think about it: RVs have built-in toilets. Williams doesn't know what he's doing. Kids love poop jokes. An honest marketing campaign could have just gone with, "It all adds up to a gusher of fecal matter!" as the poster tagline.
Director Barry Sonnenfeld gets that moment out of the way pretty early on, after a surprisingly promising opening that puts Williams on the road with his wife (Cheryl Hines, transporting her disapproving-wife shtick over from Curb Your Enthusiasm), and two kids (Josh Hutcherson and sullen-faced soul singer Joanna "JoJo" Levesque) under the false pretenses of a family vacation that's really an elaborate setup for Williams to deliver a job-threatening presentation in Boulder, Colorado. Yes, it's another overworked-dad-learns-not-to-neglect-his-kids movie, but it starts out a little more nuanced than these things usually do, and even Williams appears determined to rein in his manic impulses.
It doesn't last. Even before the sewage incident, Sonnenfeld makes it clear that the comedy's going to be as broad as possible. And after that moment, the gloves really come off. Williams and his family spend much of the film avoiding a bus-dwelling, country-music-loving, barbecue-happy family headed by Jeff Daniels and Kristin Chenoweth. Trouble is, they're a much more likeable brood than the protagonists. That's ultimately sort of the point, but it's easy to wish the camera would wander off with them instead of sticking to the stars. At least then viewers would be spared a desperate final act in which Williams first drives, then bikes, through treacherous Rocky Mountain terrain, growing sweatier with each scene.
It's one of the few moments in RV that suggests effort of any kind. Like all of Sonnenfeld's films, RV at least looks good–once a cinematographer, always a cinematographer–but the gags couldn't be more obvious if they involved the words "Knock knock." And apart from a funny turn by Arrested Development's Will Arnett as Williams' evil boss, nobody appears to be having a good time. And the feeling is infectious. When, late in the film, Williams breaks out his decades-old b-boy routine, even the shit shower starts to looks pretty good.