Michael Cera
Gunther
Jack O'Connell
Mr. Hartman
Charles Grodin
Father
Kelis
Herself
Brandon Reilly
Dougie
Curtiss Cook
Conrad
Charlotte Booker
Mrs. Hartman
Andy Prosky
Dr. Schwartz
Christina Sajous
Backup Singer
Deonna Bouyue
Backup Singer
Himanshu Suri
Recording Engineer
Andrew Levine
Adler
Adam Levite
Man in Recording Studio
Caroline Capers Powers
Dr. Schwartz's Date