Amazon Studios / Roadside Attractions

Manchester by the Sea begins with a happy memory—Lee Chandler (Casey Affleck) horsing around with his young nephew Patrick on their fishing trawler, as his brother Joe (Kyle Chandler) looks on laughing. But the action unfolds from a distance; the camera hovers far up in the sky, backed with a melancholy choral score. It’s telling of how grim Kenneth Lonergan’s new film is that, even its early, happier recollections of Lee’s life feel haunted.

Manchester by the Sea goes on to be a fantastic meditation on the long tail of trauma, but one that doesn’t wallow needlessly: There’s such humor and humanity at work that the film manages to be cathartic. Rather than focus on the lowest point in Lee’s life—the tragedy that drove him from the film’s titular town and estranged him from his wife Randi (Michelle Williams)—Lonergan moves back through time freely, showing specific moments in Lee’s past, even as he struggles with a new challenge: being a surrogate father to the now-teenaged Patrick after Joe dies.

It’s a simple-seeming setup for a family drama. Lee, who works as a janitor for an apartment complex near Boston and appears to live an emotionally spartan existence, is summoned back to the fishing town of Manchester to take care of Patrick (Lucas Hedges). The shock of Joe’s death is blunted somewhat by the knowledge that he suffered from a congenital heart condition. In flashbacks, viewers see Joe, affably played by Chandler, as the warm lynchpin of his extended family, a steadying figure whose absence feels immediate and profound. Where Joe was reliable and garrulous, Lee is prickly and taciturn, going through the mourning process as though he’s done it before.

As an actor, Affleck is terrific at showing his characters’ inner workings without saying a line—you can always see the gears ticking behind his eyes. In Lee’s case, there’s a darkness he clearly can’t shake, and the simple fact of being back in Manchester seems to be pressing in on him at every moment. Slowly, Lonergan unfolds Lee’s past, in parallel with his present efforts to abide by Joe’s wishes and serve as a guardian to Patrick, eventually revealing the nightmare that drove Lee from his hometown. It’s a sad film, but Manchester by the Sea feels like neither “misery porn” nor some academic exercise in misfortune.

That’s mostly because Lonergan keeps a firm grip on his characters, none of whom feel defined by their pain. Patrick may have just lost his father, but he remains a wise-ass 16-year-old, and his scenes with Lee have a hilarious bristle to them. Hedges is a revelation as Patrick, a willful teenager who’s juggling two girlfriends and is devoted most of all to his terrible rock band. His built-up grief spills out suddenly at random prompts, and vanishes just as quickly, startling Lee, who has gotten used to locking his feelings away.

In Patrick, Lee witnesses the grieving process playing out naturally—there’s an end in sight, even if the loss of Joe is intensely felt. For Lee, the grieving process seems more entrenched, a hard truth that’s compounded by the fact that his ex-wife Randi (Williams, extraordinary in a brief role) has gotten back on her feet with less difficulty than him. It’s best to go in to Manchester by the Sea knowing as little as possible about the Chandler family history, but it’s no spoiler to say that what transpired is horrifying enough that random townspeople in the film say, “So that’s the Lee Chandler” at the mere sight of him.

The vague mystery structure of Lonergan’s screenplay is ingenious: Run chronologically through its pile-up of family horrors, Manchester by the Sea might be too much to take. But by starting with Joe’s death, then softening the blow with flashbacks to his life, Lonergan reels viewers in rather than repelling them with hopelessness. The story of Lee’s forced exile from town becomes something you want to understand, not just another chapter of despair. It also helps that Manchester is ferociously funny throughout, thanks largely to Lee’s terse attempts at parenting Patrick.

At 2 hours and 17 minutes, the film is perhaps a bit overstuffed, meandering into some side-plots in its final act that don’t quite pay off. Lonergan’s last film, the messy 2011 masterpiece Margaret, was sprawling in all the right ways, jumping from vignette to vignette as it explored the mind of a teenager wrestling with her own psychic pain. Manchester by the Sea is a more focused work, one about Lee’s efforts to overcome his past, and his sadness at the comparative ease with which those around him have done so. In the brooding Affleck, Lonergan has found a perfect leading man, and together they’ve made a drama of rare power—a tale of human suffering that succeeds because of its love for its characters, rather than for their misfortunes.

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