Jesse Eisenberg as James Brennan

Kristen Stewart as Em Lewin

Martin Starr as Joel

Kristen Wiig as Paulette

Bill Hader as Bobby

Ryan Reynolds as Mike Connell

Margarita Levieva as Lisa P.

Jack Gilpin as Mr. Brennan

Josh Pais as Mr. Lewin

Wendie Malick as Mrs. Brennan

Mary Birdsong as Francy

Matt Bush as Tommy Frigo

Paige Howard as Sue O'Malley

Dan Bittner as Pete O'Malley

Barret Hackney as Munch

Michael Zegen as Eric

Kimisha Renee Davis as Kelly

Vanessa Hope as Ronnie Connell

Kelsey Ledgin as Arlene

Ryan McFarland as Brad

Moe Slinger as Loud Kid #1

Todd Cioppa as Velvet Touch Manager

Jesse Slinger as Loud Kid #2

Jack Baldwin as Barfing Kid

Stephen Mast as Rich

Adam Kroloff as Adult Contestant

Kevin Breznahan as Molly Hatchet T-Shirt Guy

Marc Grapey as Panda Con Dad

Andrew Ransom as Foreigner Tribute Band Member

Joe Sanderson as Foreigner Tribute Band Member

Cliff Chien as Foreigner Tribute Band Member

Russell Steinberg as Foreigner Tribute Band Member

Rob Orr as Foreigner Tribute Band Member

Eric Schaeffer as Foreigner Tribute Band Member

Gennaro DiSilvio as Nicky

Alexis Ferrante as Nicky's Girlfriend

Joe Pawlenko as Nicky's Pal

Zachary Palmer as Joel's Younger Brother

Declan Baldwin as Male Customer

Ian Harding as Wealthy Prepster

Ashtin Petrella as Prepster's Girlfriend

Amy Landis as Mrs. Ostrow

Janine Viola as Mrs. Frigo

Alana Hixson as Pretty Girl #1

Erin Cappiccie as Pretty Girl #2

Lisa Lamendola as Foxy Cougar (uncredited)

Jackson Nunn as Dancer (uncredited)