Matt Damon Rory Casey Affleck Cobby Ving Rhames Frank Toomey Jack Harlow Scalvo Michael Stuhlbarg Mr. Besegai Alfred Molina Richie Dechico Owen Earls Charlie Haggerty Hong Chau Dr. Donna Rivera Natalie Carter Mrs. Haggerty André De Shields Mr. Kelly Ron Perlman Mayor Miccelli Rob Gronkowski Rob Gronkowski Toby Jones Attorney Alan Flynn Slate Holmgren Dave Wedge Tommy Nohilly Police Commissioner Jason Furlani Cabinet Member David Gborie Bouncer Toby Onwumere John Wayne Paul Walter Hauser Booch Nathaniel Wood Massachusetts Trooper #1 Mike Bash Boston Police Officer Shawn Fitzgibbon Quincy Cop Jerry Kernion Fire Monitor Nik Walker Hero Fireman Michael Rodrick Police on the Roof Don DiPetta Officer at Airport Billy Smith New Police Commissioner John Noble Barrack Photographer Richie Moriarty Jerry the Grocer (uncredited)