Jason Clarke

as Ted Kennedy

Kate Mara

as Mary Jo Kopechne

Ed Helms

as Joseph Gargan

Bruce Dern

as Joseph Kennedy

Jim Gaffigan

as Paul Markham

Olivia Thirlby

as Rachel Schiff

Clancy Brown

as Robert McNamara

Taylor Nichols

as Ted Sorensen

John Fiore

as Chief Arena

John Curran

Director