If John Hawkes was not a household name before this year, there’s no question he will be one now, thanks to a revelatory turn in the independent dramedy “The Sessions,” opening Friday across South Florida. And if you are familiar with Hawkes from his indelible supporting roles as a junkie deadbeat in “Winter’s Bone” or a dangerous cult leader in “Martha Marcy May Marlene,” you’ll appreciate his complete 180 here – this role couldn’t be farther from these typecast backwoods creeps.

He plays Mark O’Brien, a real-life poet and journalist who completed most of his writing – pencil in mouth, one painstaking typewriter key at a time – from an iron lung, thanks to a polio diagnosis in the 1940s. With an endearingly nasally vocal pattern, thick-veined, chicken-boned arms and a convincingly curved spine, Hawkes embodies the role with remarkable commitment. He lights up whatever scene he’s in using only his face, and the artifice of acting is completely absent. He’s simplybeing– the infrequently realized goal of every actor.

“The Sessions” is set, mostly, during a few months in the 1980s, when the 38-year-old Mark attempts to see Cheryl (Helen Hunt), a “sex surrogate,” to lose his virginity over a period of six sessions. The film divides its time between Mark’s intimate meetings with Cheryl and his “confessions” (Mark was raised Catholic) to a hip priest played by William H. Macy. With the latter, the film scores its easiest laughs: Because Mark’s iron lung cannot fit in a confession booth, we’re encountered with the inevitable shocked parishioners aghast at talk of sex in the lord’s place, and we later see Macy’s Father Brendan off hours, hippie bandana around his head and clutching a six-pack. Again, easy – but it still works in a movie this infectiously charming.

The scenes between Hawkes and Hunt are the pulse of the film, though, and I can think of few instances of sex being depicted onscreen with such frankness and beauty. Hunt, nude for a good portion of the picture, gives all of herself in a role that never feels self-conscious; she and Hawkes will both receive Oscar nominations if the stars align.

But the film’s largest applause should probably be reserved for writer-director Ben Lewin, a director of indistinguishable television work who reveals himself to be a sensitive handler of actors and a warm comedic voice, tempering his film with just the right amount of melancholy (Lewin himself is an iron lung/polio survivor). It’s a studious, studied effort, one worth all the advance buzz it has received since its January premiere at Sundance.

The conclusion of the new drama “A Late Quartet” is so sublimely beautiful that it’s likely to leave just about anyone with warm hearts, teary cheeks and the affirmation that great art can trump petty grievances. If the preceding 100 minutes were half as transcendent, we might have something here.

Opening in Palm Beach County on Friday, “A Late Quartet” is about a fictional string quartet, active for 25 years and undergoing an upheaval that threatens the future of their acclaimed group. The elder statesman, Peter (Christopher Walken), has just been diagnosed with Parkinson’s disease, and his days playing music are numbered. His decision to retire at season’s end puts the other players’ emotions in flux; Robert (Philip Seymour Hoffman) is suddenly upset about his status as a second violinist, and some of his actions begin to threaten his marriage to viola player Juliette (Catherine Keener), while lead violinist Daniel (Mark Ivanir) is having his own ill-advised romantic fling with Robert and Juliette’s daughter (Imogen Poots). Old rivalries boil to the surface, new resentments flesh themselves out, and music is the last thing on anybody’s mind.

“A Late Quartet” is that rare multiplex movie for grown-ups; the problem is, we’ve seen these relationship peccadilloes before – and with the amount of times co-writer/director Yaron Zilberman telegraphs the film’s later developments, we can see them coming this time too: the husband in a fractious marriage who yields to one night of temptation in a time of struggle. The careful, dedicated workhorse whose lust for a pretty young thing clouds his better judgment. These archetypes are so well-worn they’d be rejected by Goodwill.

There’s a particularly embarrassing scene between Keener and Poots in which the mother and daughter say wicked, irredeemable things to each other, endure slaps and all but throw chairs at one another in full-on “Jerry Springer” abandon. It’s embarrassing because it’s supposed to be a crucial moment, yet it’s oddly ineffective, because their relationship had been heretofore undeveloped, leaving their tete-a-tete emotionally anchorless.

All of the actors are fine in their roles, and Walken may even be exceptional, as he’s the only one who manages to transcend the black-and-white familiarity of the film’s writing to inject some actual soul into the proceedings. An Oscar nomination would not be out of the question.

But the movie itself too often forgets what’s so special about its premise – that this is a film about a string quartet, one of the most prized cultural staples this world has had for centuries. For a movie named after this musical formation, we don’t get nearly enough notes, tempo, and color – just the same old song.