Bruce Cook as Patrick Smash

Rupert Grint as Alan A. Allen

Simon Callow as Sir John Osgood

Stephen Fry as Sir Anthony Silk

Celia Imrie as Miss Rapier

Paul Giamatti as Johnson J. Johnson

Ned Beatty as Gen. Ed Sheppard

Bronagh Gallagher as Mrs. Smash

Victor McGuire as Mr. Smash

Adam Godley as Placido P. Placeedo

Leslie Phillips as Judge

Robert Hardy as Doctor

Keira Knightley as Music School Student

Anna Popplewell as Denise Smash

Josh Herdman as Damon