History tells us Ted Kennedy’s chances of becoming president died on July l8, 1969, when Kennedy’s car drove off a bridge and plunged into the water, and his passenger, Mary Jo Kopechne, died — but some 10 hours passed before Kennedy reported the accident to police.

That’s true. Sen Edward Kennedy of Massachusetts was only 37 at the time, and he might well have been elected president in 1972 or somewhere down the line if not for the dark cloud of the Chappaquiddick scandal.

Thanks to director John Curran, screenwriters Taylor Allen and Andrew Logan and a powerfully effective ensemble cast, “Chappaquiddick” reminds us the real tragedy that night was the death of a young woman, and the real regret and outrage should be directed toward the privileged scion of an American political dynasty and everyone else who helped him minimize and excuse his unforgivable actions on that fateful night.

Jason Clarke (“Lawless,” “Zero Dark Thirty,” “Dawn of the Planet of the Apes,” “Mudbound”) is one of my favorite underappreciated actors — the type of talent who can do just about anything, but usually in a film where someone else gets the biggest showcase moments.

Yet it took me a while to warm up to Clarke’s portrayal of Ted Kennedy. Clarke drifts in and out of capturing the famous Kennedy family accent, and even though it appears he put on a little weight for the role, and the makeup and wardrobe and hairstyle are all spot-on, Clarke still seems a bit too lean and tough to play the soft and insecure Teddy.

But as the story progresses, Clarke is nothing short of great at capturing Teddy’s capacity for evoking sympathy, his talent for manipulating those who are dazzled by the Kennedy name, and his ability to focus on saving his career even as he mourns Mary Jo.

“Chappaquiddick” is told as a chronological procedural, covering the one-week period from July 18 to July 25, 1969.

During that time, the accident occurred, the cover-up and damage control efforts were put into motion, there was a media frenzy surrounding the case, Mary Jo was laid to rest, man landed on the moon (temporarily knocking the story off the front page), Kennedy pleaded guilty to a charge of leaving an accident, his sentence was suspended — and he made a statement on live television, apologizing for his actions but also making excuses, saying there might well be a curse hanging over the Kennedy family, and leaving it up to the people of Massachusetts to decide if he should continue as their senator.

“Chappaquiddick” does a remarkably economical job of encapsulating the madness of that week without overwhelming us with historical detail. The story moves from moment to moment, day to day, with clarity and great dramatic effect — and (rightfully) condemns Kennedy’s actions without turning him into a monster.

At times we almost feel sorry for Teddy, when he talks about the enormous pressure of trying to live up to the legacies of his slain brothers John and Bobby, and when he visits his elderly father Joe (Bruce Dern), who is in a wheelchair and can hardly speak, but motions for the boy to come closer — only to slap him hard across the face and tell him he was never going to be great.

Mostly, though, we’re repulsed by Teddy’s sense of entitlement, as when he takes over the local police chief’s office on the morning after the tragedy, sitting behind the chief’s desk as the chief is literally diving into the water at the scene of the accident. Not to mention his calculating attempts to gain the public’s sympathy, e.g., showing up at Mary Jo’s funeral wearing a neck brace.

Kate Mara is excellent as Mary Jo, an idealist who had worked on Bobby Kennedy’s campaign. (Mary Jo was a member of “The Boiler Room Girls,” six young women who had been a part of Bobby’s run in 1968 and agreed to attend a reunion hosted by Ted on that fateful weekend in 1969 — a party also attended by a half-dozen associates of Teddy’s, all of them much older and married. The film makes it clear nothing was going on between Ted and Mary Jo.)

Jim Gaffigan and Ed Helms turn in solid work as Ted’s closest confidants, who advise him to do the right thing but don’t push too hard when he doesn’t. Andria Blackman as Joan Kennedy has the best line in the movie, delivering the perfect response to Ted when he expresses a sentiment that’s probably 75 percent sincere and 25 percent pure B.S.

For some 46 years, Ted Kennedy was one of the most influential and effective senators in the history of the United States. He fought for noble causes and helped pass legislation championing those with disabilities, children and immigrants.

All well and good. But “Chappaquiddick” reminds us that without the Kennedy name and influence, the man who drove a car off a bridge, swam to shore and left a young woman to die, and then went into hiding and defense mode, should have gone to jail for a long time.

★★★1⁄2

Entertainment Studios presents a film directed by John Curren and written by Taylor Allen and Andrew Logan. Rated PG-13 (for thematic material, disturbing images, some strong language, and historical smoking). Running time: 101 minutes. Opens Friday at local theaters.