Mark Ruffalo
Stan
Elijah Wood
Patrick
Kate Winslet
Clementine Kruczynski
Kirsten Dunst
Mary
Jim Carrey
Joel Barish
Tom Wilkinson
Dr. Mierzwiak
Jane Adams
Carrie
Amir Ali Said
Young Bully
Debbon Ayer
Joel's Mother
David Cross
Rob
Gerry Robert Byrne
Train Conductor
Josh Flitter
Young Bully
Lola Daehler
Young Clementine
Lauren Adler
Rollerblader (uncredited)
Deirdre O'Connell
Hollis
Thomas Jay Ryan
Frank
Paulie Litt
Young Bully