In the summer of 1969, consiglieres of the former John F. Kennedy administration -- Robert McNamara, Arthur Schlesinger and Ted Sorensen, among others -- convened in Hyannis Port, Mass., to write the apology that would save the young Sen. Ted Kennedy from himself.
Only days before, Kennedy had left the scene of a fatal car crash on the small island of Chappaquiddick on Martha's Vineyard, taking the life of 28-year-old Mary Jo Kopechne.
The second-term senator waited nearly 10 hours to report the accident and offered virtually no explanation other than he "panicked."
"In those conclaves a speech, not unlike the 'Checkers' speech, was crafted for him to give on TV, throwing himself on the compassion of the American people to write and call in to keep him on the ticket," said Edward Klein, author of the new book, "Ted Kennedy: The Dream That Never Died."
"All of the Kennedy acolytes were there," Klein told ABCNews.com. "His wife Joan was not allowed downstairs. They didn't want her to hear it."
The details of the July 19 accident were salacious: a Regatta Weekend reunion party at a friend's cottage with all married men (except one) and six women -- the "boiler room girls" -- who had worked together on Robert Kennedy's 1968 presidential campaign.
After a day of sailing and heavy drinking, Kennedy drove his black Oldsmobile sedan off a small wooden bridge into Poucho Pond, trapping Kopechne in seven feet of water.
Edward Moore Kennedy -- only 38 and up for re-election the following year-- had violated one of the cardinal rules in politics: "Never get caught with a dead girl or a live boy."
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"Down through history we have had leaders who were flawed in their personal life and brilliant in public life," said Klein.
"How could he be one of most trusted members of Senate -- and they trusted his word as good as gold -- be an out-of-control frat boy most of his life?" he asked. "Life is complicated and people aren't as simple as we'd like them to be."
After that night, the word Chappaquiddick became synonymous with deception and abuse of power, and for decades until this day, each major anniversary was dredged up in newspapers around the country.
But oddly, the darkest moment in Kennedy's career also sealed his fate as a work-horse senator and ultimately transformed him into one of the most highly regarded politicians in Congress.
"For all of us, either it would make you or break you," said presidential historian Richard Norton Smith, a consultant for ABCNews.com.
"Few of us experience something as soul-testing as that, but when we can weigh it against the succeeding 40 years and draw some linkage, who would believe this story would end this way, so essentially triumphant?"