Katie Chang as Rebecca

Emma Watson as Nicki

Taissa Farmiga as Sam

Claire Julien as Chloe

Israel Broussard as Marc

Leslie Mann as Laurie

Georgia Rock as Emily

Carlos Miranda as Rob

Gavin Rossdale as Ricky

Stacy Edwards as Marc's Mom

G. Mac Brown as Henry

Marc Coppola as Mr. Hall - Marc's Dad

Janet Song as Rebecca's Mom

Annie Fitzgerald as Kate from Vanity Fair

Lorenzo Hunt as Police Officer #1 (Nicki's)

Timothy Starks as Police Officer #1 (Marc's)

Rich Ceraulo Ko as Police Officer #2 (Nicki's)

Joe Nieves as Police Officer (Rebecca's)

Nelson Rockford as Las Vegas Plainclothes Officer

Doug DeBeech as Adam

Erin Daniels as Shannon

Patricia Lentz as Judge

Michelle Alegria as Female TV Reporter #1

Stacey Turner as Female TV Reporter #2

Brian Gattas as Dogwalker

Logan Miller as Kid at Party

Marcia Ann Burrs as Grandma

Michael Yo as Male E-Interviewer

Halston Sage as School Girl

Marshall Bell as L.A. Detective #1

Brenda Koo as Sarah

Maika Monroe as Beach Girl

Isabel Lasker as Drunk Girl

Adea Lennox as Party Girl

Keenan Henson as Male TMZ Reporter

Rachelle Carson-Begley as Chloe's Mom

Peter Bigler as Chloe's Dad

Chad Brannon as Water Delivery Guy

Zoë Bleu Sidel as School Girl's Friend

Cari Champion as Female TV Reporter #3

Nina Siemaszko as Vegas Detective (Female)

Bailey Coppola as Wasted Boy

Yolanda Lloyd Delgado as Rob's Mom

Linc Hand as Police Officer Arresting Rob

Brett Goodkin as L.A. Detective #2

Paris Hilton as Paris Hilton

Kevin Spencer as Bedroom Police Officer #1

Sean Phillips as Bedroom Police Officer #2

Bobby Ashhurst as Police Officer #3

Karl Risinger as Police Officer #2 (Marc's)

Dale Champion as School Teacher

Kirsten Dunst as Kirsten Dunst (uncredited)