Lee Chandler isn’t crazy about eye contact. The Quincy, Massachusetts janitor carries himself like a person who’s taken one too many blows, a dead man walking, working, drinking and going through the motions.

Every interpersonal interaction is awkward, drawn out. He seems unfriendly simply due to reticence. But test him and an at-his-wits-end temper shows up.

It takes only the briefest of flashbacks to show how this wasn’t always so. Once upon a time, he was “cool” Uncle Lee, joshing around and mercilessly teasing his ten year-old nephew on his brother’s lobster boat, a man full of life and fun until something took it all away from him.

That was years ago, in “Manchester by the Sea.” The film that takes its title from that quaint coastal town is about Lee’s not-by-choice return to a place that haunts him and hates him.

Casey Affleck plays Lee as a man drained of all but the last hints of life, and in the opening scenes, we see him going through the motions with apartment dwellers he serves, the friendly and the unfriendly. The ones who are nice to him get nothing in return, the testy ones get told off.

His sole relief, the endless succession of beers he consumes after work.

Then he gets the phone call. His brother Joe (Kyle Chandler) is about to die. Somebody’s got to come see him, deal with a funeral. Somebody’s got to pick up Joe’s teenage son (Lucas Hedges) from hockey practice and break the news.

Lee is the last “somebody” anybody should trust with that. He is too drained of emotion, too broken to show empathy. But as Joe’s plans are laid out to him, Lee is forced to deal with his past, Joe’s death and Joe’s popular, sexually-active smart-mouthed/foul-mouthed kid, Patrick.

Writer-director Kenneth Lonergan is years and years removed from his debut success and signature film, the equally brittle and heartbroken “You Can Count on Me.” But he reminds us of his unflinching way of approaching pain and neediness with “Manchester.”

Lee and  Patrick are both closed-off, both seemingly-braced for that next awful body blow — Lee, thanks to his past, Patrick thanks to his lobsterman-dad’s long-diagnosed congenital heart disease. They need each other, and they need to be needed.

And they’re each reluctant to be the first to reach out. This is obvious from the moment Lee gives Patrick the news. Does the son want to see his father’s body?

“”Why? What’s he look like?”

“Like he’s dead. He don’t look like he’s sleeping.”

Patrick is quick to summon friends, just as quick to let the subject among them change to silly “Star Trek” debates — in “Saturday Night Light” thick Massachusetts working-class accents. Is he capable of mourning?

And he wants his girlfriend to spend the night. Is it OK?

“Is that what Joe would say?”

Every encounter, from nurses and doctors to funeral directors, family friends and Patrick, drags on into the discomfort zone. Lee can’t help it.

Lee deals, incredulously, with the family lawyer, unable to grasp why Joe would insist that he be the kid’s guardian. He tries to do his brother’s bidding, even though Joe’s demands include that he move back to this town Lee associates with pain and tragedy.

And as the flashbacks, carefully doled out, reveal, there’s an ex-wife (Michelle Williams) and an ex-life that Lee knows he’d be better off not remembering, but which he cannot forget.

Lonergan has the patience to try our patience and make us squirm at Lee’s discomfort. And Affleck so underplays Lee that he draws us in, forces us into Lee’s shoes. It’s not a fresh direction for Ben’s younger brother. He’s always given us variations of the small, still, pained man capable of disproportionate blasts of temper. But he invites pity, here, misplaced or not. And he nails the draining emptiness of grief and of a depression that will never lift.

Oscar winner Michelle Williams will tear your heart out if she lets you. And you will and she will here.

And young Hedges, best-known for TV’s “The Slap,” as well as “The Zero Theorem” and “Kill the Messenger,” brings a mercurial blend of callous sensitivity to Patrick. He’s the son of writer-director Peter Hedges, no stranger to sensitively told tales of life among the emotionally crippled (“Pieces of April,” “Dan in Real Life”). It shows.

Patrick is 16, not fully formed and needs adult guidance to show him how to react. And all the kid can bring himself to demand of his uncle is that he give up his life in Quincy, move here, give him money when he needs it, ferry him from place to place and do all that he can to facilitate Patrick’s various sexual encounters with different girls. It’s a selfish, callous veneer he wears instead of tears.

The kid needs a grownup to keep him from maturing into a jerk. Hedges walks that tightrope with skill.

Lonergan gives the film a lovely sense of place, even if he’s a bit over-fond of establishing shots reminding us that it’s winter, that this is what the river looks like frozen-over. Working class adults and children are loud, rambunctious, profane and permissive. Sex between teens is treated with little more than an adult wink.

And for such a somber and serious film, “Manchester by the Sea” can be quite playful — the comical profanity, the duologues (two people yammering away at once), the way Joe’s lobsterman friend George (C.J. Wilson) reacts when Lee abruptly asks is HE wants to be the boy’s guardian.

“I’m uh, tryin’ to LOSE some kids at this point,” George blurts out in the middle of Lee’s unfiltered plea.

What Lonergan has created here is one of the cinema’s defining statements on the kind of grief that leaves you empty, of wounds that will never heal. He’s got the guts to make us uncomfortable in scene after scene, and the courage to deny us “The Hollywood Ending.”

And Affleck, Hedges and Williams so immerse themselves in this world he’s conjured up that it is impossible to imagine it without them in it. Their scripted actions and acting reactions make “Manchester by the Sea” an exquisite cry, one of the most honest, rewarding and well-acted films of the year.

MPAA Rating:R for language throughout and some sexual content

Cast: Casey Affleck, Michelle Williams, Lucas Hedges, Kyle Chandler

Credits:Written and directed by Kenneth Lonergan. A Roadside Attractions release.

Running time: 2:17