Cast & Crew zu Dumm und Dümmehr
| Lloyd Christmas | Jim Carrey | |
| Harry Dunne | Jeff Daniels | |
| Travis / Captain Lippincott | Rob Riggle | |
| Adele | Laurie Holden | |
| Penny | Rachel Melvin | |
| Dr. Pinchelow | Steve Tom | |
| Dr. Meldmann | Don Lake | |
| Ms. Sourpuss | Patricia French | |
| Fraida Felcher | Kathleen Turner | |
| Man at Gas Station | Gregory Fears | |
| Ice Pick | Bill Murray | |
| Dr. Walcott | Tembi Locke | |
| Dr. Meldman | Paul Blackthorne | |
| Billy | Brady Bluhm | |
| Gordy | Eddie Shin | |
| Gus | Atkins Estimond | |
| Tom | Tommy Snider | |
| Professor Garabedian | Lindsay Ayliffe | |
| Inventor No. 1 | Matthew Cardarople | |
| Harry's Dad | Michael Yama | |
| Harry's Mom | Nancy Yee | |
| Mr. Stainer | Grant James | |
| Mrs. Stainer | Taylor St. Clair | |
| Asylum Nurse No. 1 | Erin Allin O'Reilly | |
| Asylum Nurse No. 2 | Nancy Byers Farrelly | |
| Young Harry | Dalton E. Gray | |
| Harry's Trailer Park Wife | June Shannon | |
| Young Fraida | Carly Craig | |
| Trophy Wife/Mrs. Rhode Island | Allison Freitas | |
| Regie |
Bobby Farrelly Peter Farrelly |
|
| Buch |
Sean Anders Mike Cerrone Bobby Farrelly Peter Farrelly John Morris Bennett Yellin |
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| Kamera |
Matthew F. Leonetti |
|
| Schnitt |
Steven Rasch |
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