THERE'S A REASON mumblecore films have been referred to more aptly as "the new talkies." In addition to shaky handheld camerawork, improvised performances, and unprofessional actors, the films' verité qualities extend to the subject matter of the dialogue. Characters are continually getting real, obsessively processing their relationships, vetting their flaws. At its best, this rawness can be arresting, relatable, and touching, showing up typical relationship and personality dramas as conservative, over-groomed, and sterile. It helps to have something interesting to talk about, though—and quizzically, Cyrus ignores the most interesting elements of its premise. Instead of blowing the doors off Hollywood standards, mumblecore auteurs/stars Jay and Mark Duplass' studio debut squeaks in rather shyly (arguably an indication that their future in mainstream film has legs, if you want to get cynical about it).

The biggest film thus far from the talkie crowd, Cyrus has extremely high expectations attached to it. Those who've been cheerleading the films of this underground genre—not to mention fans of Cyrus' cult favorites John C. Reilly, Marisa Tomei, Jonah Hill, and Catherine Keener—want it to be the breakout film they've been waiting for. And it is a legitimization of the style, at least, and the cast members' presences are a weighty endorsement, though the film seems to choke a bit on its good fortune.

It's difficult to believe, for instance, that Reilly and Tomei were cast as a couple because it works, not just because the Duplasses could get them. This central unlikelihood is exacerbated by the film going to pains to introduce Reilly's character John as a lonely slob, with an opening scene that has his ex-wife (Keener, also unlikely) accidentally walking in on him masturbating in a filthy bachelor pad. Tomei plays Molly, whose tight (like, creepy tight) relationship with her son Cyrus (played by Hill, who's believable if prone to slipping into shtick) is what has kept her single. But aside from that, and for all the unpacking these people do, we learn almost nothing about Molly, or who Cyrus' father is, or what Molly does for a living or why her relationship with her son is peculiar or what she sees in John. The duplicitous Cyrus is as much a mystery.

Throughout, John's perspective is both the least complicated and the only one we're made privy to. Despite the multitude of unknowns, untapped territory is passed over for the straightforward dynamic Cyrus focuses on, when we expected a twist. It's not a bad film, but we're familiar with stories about love triangles created by jealous, threatened mama's boys. This one just talks more.