Matt Damon

Character: Rory

Casey Affleck

Character: Cobby

Ving Rhames

Character: Frank Toomey

Jack Harlow

Character: Scalvo

Michael Stuhlbarg

Character: Mr. Besegai

Alfred Molina

Character: Richie Dechico

Owen Earls

Character: Charlie Haggerty

Hong Chau

Character: Dr. Donna Rivera

Natalie Carter

Character: Mrs. Haggerty

Walter Liebman

Character: Terry

André De Shields

Character: Mr. Kelly

Ron Perlman

Character: Mayor Miccelli

Rob Gronkowski

Character: Rob Gronkowski

Toby Jones

Character: Attorney Alan Flynn

Slate Holmgren

Character: Dave Wedge

Ronnie Cho

Character: Mark Choi

Sheika Murray

Character: Waiter #1 at Wharf

Perry Strong

Character: Waiter #2 at Wharf

Nick Trice

Character: City Hall Employee

Tommy Nohilly

Character: Police Commissioner

Jason Furlani

Character: Cabinet Member

David Gborie

Character: Bouncer

Toby Onwumere

Character: John Wayne

Paul Walter Hauser

Character: Booch

Scout Backus

Character: Colani

Nicholas B Alexander

Character: Sergeant at Rivera's Office

Nathaniel Wood

Character: Massachusetts Trooper #1

Craig Hutchinson

Character: Massachusetts Trooper #2

Mike Bash

Character: Boston Police Officer

Deirdre McCourt

Character: Vermont Cop

Shawn Fitzgibbon

Character: Quincy Cop

Jerry Kernion

Character: Fire Monitor

Nik Walker

Character: Hero Fireman

Ramona Floyd

Character: Bartender

Mark Steven Dancewicz

Character: Tactical Cop

Brett Keating

Character: Sniper in Tower

Michael Rodrick

Character: Police on the Roof

Eleni Yiovas

Character: Senior Tactical Cop

Gregory Cunningham

Character: Senior Cop at Plaza

Peter Morse

Character: Cop at Barricade

Robert Marsella

Character: Cop That Says Hey

Don DiPetta

Character: Officer at Airport

Christopher Brian Roach

Character: Police Transfer Officer

Billy Smith

Character: New Police Commissioner

John Noble Barrack

Character: Photographer

Jadon Cole

Character: Rory's Son

Robbie Dema

Character: Border Patrol Mountie #1

Robert Harvey

Character: Border Patrol Mountie #2

Jonathan Gabriel Charles

Character: Pollster

Craig 'Radio Man' Castaldo

Character: Self (uncredited)