| Paul Giamatti | ... Barney Panofsky |
|
| Rosamund Pike | ... Miriam Grant Panofsky |
| Minnie Driver | ... The 2nd Mrs. P |
| Rachelle Lefevre | ... Clara "Chambers" Charnofsky |
| Scott Speedman | ... Boogie |
| Bruce Greenwood | ... Blair |
| Macha Grenon | ... Solange |
| Anna Hopkins | ... Kate Panofsky |
| Jake Hoffman | ... Michael Panofsky |
| Mark Addy | ... Det. O'Hearne |
| Saul Rubinek | ... Charnofsky |
|
| Thomas Trabacchi | ... Leo |
| Clé Bennett | ... Cedric |
| Harvey Atkin | ... 2nd Mrs. P's Father |
| Massimo Wertmüller | ... Rome Doctor |
| Howard Jerome | ... Uncle Irv |
| Linda Sorenson | ... 2nd Mrs. P's Mother |
|
| and |
| Dustin Hoffman | ... Izzy Panofsky |
|
| Paul Gross | ... Constable O'Malley of the North |
| Atom Egoyan | ... O'Malley Director #1 |
| Mark Camacho | ... TU Productions Executive #1 |
| David Pryde | ... TU Productions Executive #2 |
| Paula Jean Hixson | ... Bartender at Grumpy's |
| Marica Pellegrinelli | ... The Countess |
| Domenico Minutoli | ... Judge at Rome Wedding |
| Sam Stone | ... Fundraising Target #1 |
| Burney Lieberman | ... Fundraising Target #2 |
| Morty Bercovitch | ... Fundraising Target #3 |
| Pauline Little | ... 2nd Mrs. P's Housekeeper |
| Robin Kazdan | ... Wedding Guest |
| Maury Chaykin | ... Wedding Guest |
| Larry Day | ... Bartender at Wedding |
| Sheila Hymans | ... Rabbi's Wife |
| Len Richman | ... Rabbi |
| Howard Rosenstein | ... Cousin Jeff |
| Ted Kotcheff | ... Train Conductor |
| Brittany Lee Drisdelle | ... Girl at Cafe |
| David Cronenberg | ... O'Malley Director #2 |
| Kyle Switzer | ... Production Assistant |
| Rebecca Croll | ... Receptionist #1 |
| Steve Bienstock | ... NY Restaurant Waiter |
| Arthur Holden | ... Notary |
| Zack Kifell | ... Young Michael Panofsky |
| Simone Richler | ... Young Kate Panofsky |
| Denys Arcand | ... Maître D at Ritz |
| Arthur Grosser | ... Mr. Dalhousie |
| Pascale Bourbeau | ... Woman at Cemetery |
| Ellen David | ... Massage Parlor Madame |
| Katia Di Perna | ... Masseuse |
| Marina Eva | ... Leo's Girlfriend |
| Sandra Lavoie | ... Barney's One Night Stand |
| Harry Standjofski | ... Dr. Morty |
| Ivana Shein | ... Receptionist #2 |
| Melanie St-Pierre | ... O'Malley’s New Co-Star |
| Tarah Schwartz | ... Reporter |
| Richard Lewis | ... Pathologist |
