Michael Keaton Samuel Finnix Actor, Executive Producer Rosario Dawson Bridget Meyer Actor Peter Sarsgaard Rick Mountcastle Actor Kaitlyn Dever Betsy Actor Will Poulter Billy Actor John Hoogenakker Randy Ramseyer Actor Michael Stuhlbarg Richard Sackler Actor Mare Winningham Diane Mallum Actor Beth Macy Executive Producer Warren Littlefield Executive Producer Danny Strong Executive Producer John Goldwyn Executive Producer Karen Rosenfelt Executive Producer Barry Levinson Executive Producer Jessica Mecklenburg Co-Executive Producer Mandy Safavi Co-Executive Producer Peter H. McGuigan Producer Richie Kern Producer