Paul Giamatti

as Paul Hunham

Dominic Sessa

as Angus Tully

Da'Vine Joy Randolph

as Mary Lamb

Carrie Preston

as Miss Lydia Crane

Brady Hepner

as Teddy Kountze

Ian Dolley

as Alex Ollerman

Jim Kaplan

as Ye-Joon Park

Michael Provost

as Jason Smith

Andrew Garman

as Dr. Hardy Woodrup

Naheem Garcia

as Danny

Stephen Thorne

as Thomas Tully

Gillian Vigman

as Judy Clotfelter

Tate Donovan

as Stanley Clotfelter

Darby Lee-Stack

as Elise

Bill Mootos

as Mr. Endicott

Dustin Tucker

as Mr. Rosensweig

Juanita Pearl

as Mary's Sister Peggy

Alexander Cook

as Priest / Bartender

Liz Bishop

as Office Lady

Cole Tristan Murphy

as Toothbrushing Student

Will Sussbauer

as Cobb Salad Student

Carter Shimp

as Weed Buyer Harriman

Michael Malvesti

as Christmas Tree Guy

Dakota Lustick

as Christmas Tree Helper

Melissa McMeekin

as Hooker

Jonathan von Mering

as ER Doctor

Rena Maliszewski

as ER Nurse

Osmani Rodriguez

as Pharmacist

Oscar Wahlberg

as Pinball Player

Dan Aid

as Vietnam Vet Kenneth

Mike Kaz

as Hip Party Guest

Kelly AuCoin

as Hugh Cavanaugh

Colleen Clinton

as Mrs. Cavanaugh

Fred Robbins

as Santa Claus

David J. Curtis

as Psychiatric Orderly

Pamela Jayne Morgan

as Waitress

Davis Robinson

as Maître d'hôtel

Joe Howell

as Liquor Store Cashier

Peter Krasinski

as Choir Leader

Greg Chopoorian

as Jason Smith's Father

Ian Lyons

as Miss Crane's Boyfriend

Kevin Fennessy

as Irritated Movie Patron

Kevin Daigneault

as Barton Parent (uncredited)

Bhanu Gopal

as Boston Streeter / Pedestrian (uncredited)

Quinn Stone

as Student (uncredited)

Lily Steven

as Kristy (uncredited)