On December 14, 2015, it was announced that Sam Taylor-Johnson would direct the film, though she later dropped out. On April 25, 2016, it was announced Jason Clarke would play Ted Kennedy, with John Curran directing. On July 7, 2016, Kate Mara and Ed Helms joined the cast, to play Mary Jo Kopechne and Joe Gargan, respectively. On July 20, 2016, Bruce Dern was added as Joseph P. Kennedy Sr., while Jim Gaffigan and Olivia Thirlby joined the cast on August 31, 2016, and principal photography began in Boston on September 7, 2016.