Megan Fox

Jennifer

Amanda Seyfried

Needy

Johnny Simmons

Chip

Adam Brody

Nikolai

Sal Cortez

Chas

Ryan Levine

Mick

Juan Riedinger

Dirk

Colin Askey

Keyboardist

Chris Pratt

Roman Duda

Juno Rinaldi

Officer Warzak

Kyle Gallner

Colin Gray

Josh Emerson

Jonas Kozelle

J.K. Simmons

Mr. Wroblewski

Amy Sedaris

Needy's Mom

Cynthia Stevenson

Chip's Mom

Nicole Leduc

Camille

Aman Johal

Ahmet from India

Dan Joffre

Raymundo

Candus Churchill

Nutritionist

Carrie Genzel

Jennifer's Mom

Emma Gallello

Little Jennifer

Megan Charpentier

Little Needy

Jeremy Schuetze

Craig

Valerie Tian

Chastity

Emily Tennant

Gossiping Girl

Karissa Tynes

Other Girl

Eve Harlow

Goth Girl

Michael Brock

Goth Boy

Genevieve Buechner

Goth Girl #2

Adrian Hough

Colin's Dad

Gabrielle Rose

Colin's Mom

Michael Bean

Priest

Bill Fagerbakke

Jonas' Dad

Marilyn Norry

Jonas' Mom

Cut Chemist

DJ at Dance

Zoe LaLiberté

Candlelight Vigil Singer

Chelsey Smith

Candlelight Vigil Singer

Whitney Chow

Candlelight Vigil Singer

Michael Orstad

Candlelight Vigil Singer

Ronnie Robinson

Orderly

Ed Anders

Orderly

Roxanne Wong

Patient #1

Diane Dutra

Patient #2

Maya Toews

The Creepy Hand

Diablo Cody

Melody Lane Drinking Woman (uncredited)

Lance Henriksen

Passing Motorist (uncredited)