Jim Caviezel John Reese Actor Michael Emerson Harold Finch Actor Kevin Chapman Lionel Fusco Actor Sarah Shahi Sameen Shaw Actor Amy Acker Root Actor John Nolan John Greer Guest Star Quinn Shephard Claire Mahoney Guest Star Bella Dayne Anna Mueller Guest Star Ayana Workman Receptionist Guest Star Nick Westrate Calvin Mazer Guest Star Heléne Yorke Lauren Buchanan Guest Star Omar Maskati Naresh Prasad Guest Star Kay Tauginas Alek Guest Star Andrew Criss Referee Guest Star Patrick Brana Gym Front Desk Guy Guest Star Derrick Williams Barden Guest Star Kenneth McCoy Busy Coder Guest Star Fiona Choi Samaritan Tech Guest Star Louis Lourens Samaritan Representative Guest Star J.J. Abrams Executive Producer Bryan Burk Executive Producer Jonathan Nolan Executive Producer David Semel Executive Producer Greg Plageman Executive Producer Dan Dietz Writer Steve Semel Director