Joining the cast are Liev Schreiber as President Lyndon B. Johnson; Minka Kelly (Jackie Kennedy); Melissa Leo (Mamie Eisenhower); James Marsden (JFK); Mariah Carey, Vanessa Redgrave; Alex Pettyfer, Yaya DaCosta, Elijah Kelly, and Jesse Williams.

As previously reported, the film will star Forest Whitaker as Allen, with Oprah Winfrey as Allen's wife, Robin Williams (President Dwight D. Eisenhower); John Cusack (President Richard Nixon); Alan Rickman (Ronald Reagan); Jane Fonda (Nancy Reagan);Colman Domingo, Cuba Gooding Jr, David Oyelowo, and Lenny Kravitz.