Liam Neeson as Mark Felt

Diane Lane as Audrey Felt

Maika Monroe as Joan Felt

Wendi McLendon-Covey as Carol Tschudy

Julian Morris as Bob Woodward

Josh Lucas as Charlie Bates

Tony Goldwyn as Ed Miller

Kate Walsh as Pat Miller

Michael C. Hall as John Dean

Marton Csokas as Pat Gray

Tom Sizemore as Bill Sullivan

Ike Barinholtz as Angelo Lano

Bruce Greenwood as Sandy Smith

Brian d'Arcy James as Robert Kunkel

Noah Wyle as Stan Pottinger

Eddie Marsan as Agency Man

Wayne Pére as John Ehrlichman

Stephen Michael Ayers as John Mitchell

Darryl Cox as Richard Kleindienst

Scott Poythress as Gray's Flack

Jeff Sprauve as Undercover Agent

Frank Hoyt Taylor as Senator #1

Charles Green as Reverend

Michael Crider as Senator #2

John Chancellor as Self (archive footage) (uncredited)

Walter Cronkite as Self (archive footage) (uncredited)

Richard Nixon as Self (archive footage) (uncredited)

Pat Nixon as Self (archive footage) (uncredited)

Jessica Young as Joan's Friend

Spiro Agnew as Self (archive footage - uncredited)