‘Cyrus’ stars bring a believable ring

A comedy of discomfort that walks a wonderful line between reality-based emotional honesty and engaging humor, “Cyrus” demonstrates the good things that happen when quirky independent style combines with top-of-the-line acting skill.

That style belongs to the writing-directing brother team of Jay and Mark Duplass, stalwarts of the bargain-basement approach often called “mumblecore.” Their work in films such as “The Puffy Chair” and “Baghead” involves free-floating camerawork and actors willing to improvise off a written script, all with an eye to heightening the authenticity of their stories.

In “Cyrus,” with a cast that includes gifted veterans John C. Reilly, Marisa Tomei and Catherine Keener as well as relative newcomer Jonah Hill, they have moved up from their shambling roots and made something satisfying and substantial.

Reilly’s John is surprised in an intimate sexual moment by his ex-wife and best friend Jamie (Keener), who arrives at his house unannounced to tell him that after seven years she is remarrying.

John may come off as a hapless, borderline- desperate guy, but Reilly lets us know there is a core of value in him just waiting to be awakened and embraced.

Primed to cause that awakening, or so it seems, is Tomei’s irresistible, engaging Molly. The two meet cute at a party and end up in bed. There’s just one hitch: her life is complicated, she says.

The complication is named Cyrus (smartly played by Judd Apatow alumnus Hill), Molly’s nearly 22-year-old son, who still lives at home with no sign of leaving.

Is Cyrus trying to break up the lovers? Is John over his head in a comic psychodrama not of his own choosing?

Beautifully played by all three principals, who understand where the warmth, the laughs and the conflicts lie, “Cyrus” is a relationship drama that rings all the truer for being one we have not seen before. And will not soon forget.