The fascination with the Kennedy political dynasty continues in this suspenseful drama; Chappaquiddick reconstructs events around a car accident which left a young woman dead and ruined Ted Kennedy's hopes for a presidential run.
In 1969 the senator is being groomed by his ruthless father, Joe, to run for president in 1972. Edward "Ted" Kennedy (Jason Clarke), the youngest of the Kennedy clan, organises a party at a house in Martha's Vineyard for a group of young political strategists and campaign workers, including Mary Jo Kopechne (Kate Mara).
During the evening Ted and Mary Jo take a ride - there's an insinuation they may have been romantically involved - and on their way back Ted drives off a bridge. Ted escapes the accident but Mary Jo is trapped in the car and drowns. It took Ted eight hours to report the accident, by which time Mary Jo's body had already been recovered.
This relatively clinical and restrained film speculates on what happened during those eight hours and following days, as Ted, his powerful family and inner circle, including John F. Kennedy's speechwriter Ted Sorensen and Robert McNamara, former US Secretary of Defence, do everything possible to save Ted's reputation.
Their behavior is reprehensible, evidencing the cowardice and shallowness of the youngest Kennedy son, and the incredible sense of power and entitlement surrounding the Kennedy family.