A nuanced portrait of Kennedy during one of the worst (and most formative) events of his life.

Playing a public figure is always a big gamble, and a Kennedy — with those faces, those jaws, that peculiar accent that’s so easy to exaggerate — has long been a waystation for actors looking to prove their chops. In John Curran’s “Chappaquiddick,” Jason Clarke opts for a more low-key approach to Teddy Kennedy, eschewing a big accent or showy mannerisms, and fully disappears into the role. It’s his finest work yet, and proof of his ability to excel given the right material.

And what material he’s got, thanks to a tight script from Taylor Allen and Andrew Logan that dramatizes the events surrounding the fatal 1969 event that took place on the Martha Vineyard’s peninsula from which the film derives its title. Compellingly directed by Curran, “Chappaquiddick” takes place over the course of a single week, following a young Senator Kennedy before, during, and after the car accident that claimed the life of former aide Mary Jo Kopechne (Kate Mara), who worked on his brother Bobby’s campaign before he was assassinated the year before.

While the finer details surrounding the late-night car accident that killed Kopechne have long remained fuzzy, Allen and Taylor’s script builds off the known factors, crafting a nuanced portrait of Kennedy during one of the worst (and most formative) events of his life.

Curran approaches the material with a pointed perspective that lays bare all of Teddy’s worst impulses and tragic obsessions. “Chappaquiddick” is just as consumed by the various theories as to what scars mark the Kennedys as America has been for decades, but Curran confidently layers on the various forces – reputation, legacy, hubris, family – that push and pull Teddy not just from choice to choice, but moment to moment.

Joe Kennedy (Bruce Dern, perfectly calibrated as ever) looms most immediately over the plot, a felled giant who literally whispers terrible ideas into Teddy’s ear, but other ghosts haunt every moment. From Bobby and Jack’s deaths to his crumbling marriage, his lack of desire to be president and his wish to be his own man, Teddy can’t get out from under the weight of the world, even though he remains convinced that he’s still got some sort of special Kennedy compass guiding him. It mostly guides him woefully astray.

Whenever Clarke is on screen, darkness finds its way into the frame, an inky blankness that turns the most benign of shadows into black holes. But “Chappaquiddick” revels in the gray areas, offering up a version of the story that doesn’t demand full acceptance, but still presents a take on the material with a distinct point of view.

Most damning towards Kennedy, however, is that Allen and Logan’s script repeatedly finds the space for Teddy to make the right decision, often edging so close to it that the film seems close to rewriting actual historical fact, before bending back to choices that only serve to protect his own interests, and at great cost. That Teddy knew the right thing to do and refused to carry through is the film’s consistent message, though it’s never delivered in a heavy-handed manner.

Clarke and Dern are joined by Ed Helms and Jim Gaffigan as the film’s major players, and the two actors are fine matches for both, Helms in particular as Kennedy cousin Joe Gargan, who in Curran’s telling also saw his life ruined by the events of that weekend. Mara’s Mary Jo is mostly relegated to background noise — appropriate, considering how the real Kopechne was nearly forgotten as the scandal unfolded in the face of Kennedy’s blustering — though Curran includes her in a handful of compelling postmortem scenes, including a particularly moving sequence that imagines her final moments.

Constrained to that single week, “Chappaquiddick” drives to the historically and emotionally inevitable: Kennedy’s televised statement about the incident, delivered to all the major stations just days after it happened. Clarke does wonders with the material, adding new dimensions and layers between what hit the screen and what lingered just out of frame. As he implores his citizens to hold faith, his own finally slips away, the damage forever done.

Grade: A-

“Chappaquiddick” had its world premiere at the 2017 Toronto International Film Festival. Entertainment Studios acquired the film at the festival.

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