Michael Stuhlbarg

as Larry Gopnik

Richard Kind

as Uncle Arthur

Fred Melamed

as Sy Ableman

Sari Lennick

as Judith Gopnik

Aaron Wolff

as Danny Gopnik

Jessica McManus

as Sarah Gopnik

Peter Breitmayer

as Mr. Brandt

Brent Braunschweig

as Mitch Brandt

David Kang

as Clive Park

Benjamin Portnoe

as Danny's Reefer Buddy

Jack Swiler

as Boy on Bus

Andrew S. Lentz

as Cursing Boy on Bus

Jon Kaminski Jr.

as Mike Fagle

Ari Hoptman

as Arlen Finkle

Alan Mandell

as Rabbi Marshak

Amy Landecker

as Mrs. Samsky

George Wyner

as Rabbi Nachtner

Michael Tezla

as Dr. Sussman

Katherine Borowitz

as Friend at the Picnic

Steve Park

as Clive's Father

Allen Lewis Rickman

as Shtetl Husband

Yelena Shmulenson

as Shtetl Wife

Fyvush Finkel

as Dybbuk?

Ronald Schultz

as Hebrew School Teacher

Raye Birk

as Dr. Shapiro

Jane Hammill

as Larry's Secretary

Claudia Wilkens

as Marshak's Secretary

Simon Helberg

as Rabbi Scott

Adam Arkin

as Divorce Lawyer

James Cada

as Cop #1

Michael Lerner

as Solomon Schlutz

Charles Brin

as Hebrew School Principal

Michael Engel

as Torah Blesser

Tyson Bidner

as Magbiah

Phyllis Harris

as Hebrew School Tea Lady

Piper Sigel-Bruse

as D'vorah

Hannah Nemer

as Sarah's Friend

Rita Vassallo

as Law Firm Secretary

Warren Keith

as Dick Dutton (voice)

Neil Newman

as Cantor

Tim Russell

as Detective #1

Jim Lichtscheidl

as Detective #2

Wayne A. Evenson

as Russell Krauss

Scott Thompson Baker

as Sci-Fi Movie Hero

Landyn Banx

as Physics Student (uncredited)

Punnavith Koy

as Physics Nerd (uncredited)

Joel Thingvall

as Bar Mitzvah Guest (uncredited)

Amanda Day

as Physics Student (uncredited)