Paul Giamatti
Role: Paul Hunham
Dominic Sessa
Role: Angus Tully
Da'Vine Joy Randolph
Role: Mary Lamb
Carrie Preston
Role: Miss Lydia Crane
Brady Hepner
Role: Teddy Kountze
Ian Dolley
Role: Alex Ollerman
Jim Kaplan
Role: Ye-Joon Park
Michael Provost
Role: Jason Smith
Andrew Garman
Role: Dr. Hardy Woodrup
Stephen Thorne
Role: Thomas Tully
Gillian Vigman
Role: Judy Clotfelter
Tate Donovan
Role: Stanley Clotfelter
Darby Lee-Stack
Role: Elise
Bill Mootos
Role: Mr. Endicott
Dustin Tucker
Role: Mr. Rosensweig
Juanita Pearl
Role: Mary's Sister Peggy
Alexander Cook
Role: Priest / Bartender
Liz Bishop
Role: Office Lady
Cole Tristan Murphy
Role: Toothbrushing Student
Will Sussbauer
Role: Cobb Salad Student
Carter Shimp
Role: Weed Buyer Harriman
Michael Malvesti
Role: Christmas Tree Guy
Dakota Lustick
Role: Christmas Tree Helper
Melissa McMeekin
Role: Hooker
Jonathan von Mering
Role: ER Doctor
Rena Maliszewski
Role: ER Nurse
Osmani Rodriguez
Role: Pharmacist
Oscar Wahlberg
Role: Pinball Player
Dan Aid
Role: Vietnam Vet Kenneth
Mike Kaz
Role: Hip Party Guest
Kelly AuCoin
Role: Hugh Cavanaugh
Colleen Clinton
Role: Mrs. Cavanaugh
Fred Robbins
Role: Santa Claus
David J. Curtis
Role: Psychiatric Orderly
Pamela Jayne Morgan
Role: Waitress
Davis Robinson
Role: Maître d'hôtel
Joe Howell
Role: Liquor Store Cashier
Peter Krasinski
Role: Choir Leader
Greg Chopoorian
Role: Jason Smith's Father
Ian Lyons
Role: Miss Crane's Boyfriend
Kevin Fennessy
Role: Irritated Movie Patron
Kevin Daigneault
Role: Barton Parent (uncredited)
Bhanu Gopal
Role: Boston Streeter / Pedestrian (uncredited)