Tom (Joel McHale) and Janet (Kerry Bishé) appear to have the perfect marriage. Even after 14 years together, the main characters of writer-director BenDavid Grabinski’s Happily are still so hot for each other that they can’t resist having sex in the bathroom at a friend’s party. They are patient, kind and loving with each other at home. After Tom makes a slightly insensitive request one morning, by the time Janet comes home from work he’s cleaned the entire house, done the laundry and lit the bedroom with candles in order to make up for it. And none of it is an act -- they really do love each other this much.

So naturally, they drive the people around them crazy. “Everyone hates you,” says their alleged friend Karen (Natalie Zea) when they’re out to dinner with Karen and her husband Val (Paul Scheer). Tom and Janet are supposed to join four other couples, including Karen and Val, for a weekend getaway, but they’ve been uninvited because of how annoying they are. Other people think that their happy relationship is somehow unnatural, and that sense is confirmed when a mysterious man (Stephen Root) shows up at their house claiming to be the agent of a higher power.

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The man says that the universe has somehow made a mistake placing the two of them together, and that the gradual diminishing of affection in a marriage is the correct order of things. He tells them they’ll be required to inject themselves with a glowing serum that will make them “normal,” and offers them financial compensation in return for their trouble. At this point, still early in the movie, Happily has already made at least a couple of genre shifts, from relationship comedy to existential drama to science fiction, and Grabinski never stops messing with audience expectations.

Stephen Root in Happily

Instead of obeying the orders from this possibly supernatural intruder, Karen assaults him, and then the couple goes on the run, attempting to hide out at the couples’ retreat that they’ve been suspiciously reinvited to. The longest stretch of Happily is structured as a sort of dark crime comedy, as Tom and Karen worry about whether they’ve successfully covered up their violent act, and whether one or more of their friends actually sent the man as a sort of cruel prank, and not as a message from the universe. Despite the often sardonic tone, though, the movie is more bizarre than funny. Happily then switches gears a few more times before it ends, eventually becoming as grim and serious as a horror movie, with Root as the characters’ Jigsaw-like tormentor.

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For a while, it’s exciting to see where Grabinski is going to take things next, and Happily is impressively assured for a directorial debut (Grabinski has worked as a screenwriter, and is the creator of the recent Nickelodeon Are You Afraid of the Dark? revival). Grabinski assembles a fantastic cast, with Natalie Morales, Jon Daly, Shannon Woodward, Kirby Howell-Baptiste, Breckin Meyer and Charlyne Yi as the other couples staying at an ultra-fancy (and, of course, ominous) vacation home. Morales is especially amusing as the friend who organized the weekend and seems to take every crazy development in the story completely in stride.

Joel McHale and Kerry Bishe in Happily

Viewers can take those crazy developments in stride for a while, too, and it helps that Grabinski also has an eye-catching visual style, with vibrant colors and striking production design. But the balancing act starts to wobble as Happily goes on, and Grabinski has to follow through on the strange world he’s created. Root in particular is underused as the enigmatic puppet master, and the eventual outcome of the plot is frustrating and incomplete. It seems to be a deliberate choice on Grabinski’s part, but that doesn’t make it any less dissatisfying, especially when Happily has failed to develop any of the supporting characters the way it does Tom and Janet.

Grabinski makes poor use of his stacked lineup of actors, who never get the chance to earn the revelations that Happily doles out in its finale. There’s no reason to care about any of these people aside from Tom and Janet, and even that main couple is presented as possible misguided aberrations rather than fully formed people. Grabinski seems fixated on keeping the audience on its toes, so much so that he neglects to construct a cohesive narrative. One particular development among characters who’ve barely had a handful of lines each is so heavy yet so abrupt that it borders on distasteful.

Yet there’s no denying the stylistic appeal of Happily, and at least Grabinski displays too much ambition in his first feature, rather than too little. If he can put together a lineup of actors this good, shoot them with the same inventiveness, and back that up with a story that is both audacious and coherent, he’ll have an unbeatable formula for his next movie.

Starring Joel McHale, Kerry Bishé, Natalie Zea, Paul Scheer, Natalie Morales, Jon Daly, Shannon Woodward, Kirby Howell-Baptiste, Breckin Meyer, Charlyne Yi and Stephen Root, Happily opens Friday, March 19 in select theaters and on VOD.

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