A protégé of both Disney composer Buddy Baker and television composer Mike Post, Debney began his career doing music for rides at Disneyland and Walt Disney World. After leaving Disney, Debney went into television (scoring for shows ranging from Star Trek: The Next Generation* to much of the Hanna-Barbera output). While serving as a composer for Hanna-Barbera, he did his first major film Jetsons: The Movie (having previously done the likes of Seven Hours To Judgment and The Further Adventures Of Tennessee Buck). He went into film full-time after James Horner recommended him to score Hocus Pocus (1993) three years later and got his big break when he replaced David Arnold on 1995's Cutthroat Island (Debney is just about the only person involved with this film whose career didn't take a body blow as a result).
Steadily working since then, he has tackled multiple genres and is known to adapt to any style given to him. He also mentored director Robert Rodriguez on scoring and has collaborated with him on a few scores. Debney has received an Oscar nomination for The Passion of the Christ and won three Emmys, for The Cape (1996), SeaQuest DSV and The Young Riders. He is currently one of the composers working on The Orville.
Debney also has the distinction of having written music for Star Trek, Doctor Who, DC (he scored the ill-fated Justice League of America pilot) and Marvel (Iron Man 2)! And he also scored the pilot of Young Sheldon (thanks to being the director Jon Favreau's Associated Composer).
Among the films scored by Debney:
- Jetsons: The Movie (1990)
- Hocus Pocus (1993) (1993) - with James Horner supplying "Sarah's Theme" - and Hocus Pocus 2 (2022) - Emmy Award nominee for the sequel.
- White Fang 2: Myth of the White Wolf (1994)
- Little Giants (1994)
- Cutthroat Island (1995)
- Sudden Death (1995)
- The Relic (1997)
- Liar Liar (1997) - theme by James Newton Howard
- I Know What You Did Last Summer (1997)
- Inspector Gadget (1999)
- My Favorite Martian (1999) - with Danny Elfman providing "Uncle Martin Theme".
- Dick (1999)
- The Adventures of Elmo in Grouchland (1999)
- End of Days (1999)
- The Replacements (2000)
- The Emperor's New Groove (2000)
- G-Saviour (2000) with Louis Febre.
- Spy Kids and its first sequel (2001, 2002) - with Robert Rodriguez (both films), Danny Elfman (first film) and Harry Gregson-Williams (first film)
- Cats & Dogs (2001)
- The Princess Diaries and its sequel (2001, 2004)
- Heartbreakers (2001) - main theme by Danny Elfman
- Jimmy Neutron: Boy Genius (2001)
- Snow Dogs (2002)
- The Scorpion King (2002)
- Swimfan (2002) - themes only. (Film scored by Louis Febre)
- The Tuxedo (2002) - with Christophe Beck
- The Hot Chick (2002)
- Bruce Almighty and Evan Almighty (2003, 2007)
- Elf (2003)
- Looney Tunes: Back in Action (2003) - last quarter only (rest of the film scored by Jerry Goldsmith)
- The Passion of the Christ (2004) - nominated for Academy Award
- Spider-Man 2 and Spider-Man 3 (2004, 2007) - with Danny Elfman (2 only) and Christopher Young (2 and 3)
- Sin City (2005) - with Robert Rodriguez and Graeme Revell (Debney only scored the segment "The Big Fat Kill").
- Chicken Little (2005)
- Zathura (2005)
- Duma (2005) - with George Acogny
- The Mummy: Tomb of the Dragon Emperor (2008) - Additional music only (film scored by Randy Edelman)
- Hotel for Dogs (2009)
- Hannah Montana: The Movie (2009)
- Valentine's Day (2010)
- Iron Man 2 (2010)
- Predators (2010) - also adapted Alan Silvestri's theme
- Machete (2010) - with Robert Rodriguez and his band, Chingon
- Yogi Bear (2010)
- No Strings Attached (2011)
- The Change-Up (2011) - with Theodore Shapiro
- Dream House (2011)
- New Year's Eve (2011)
- A Thousand Words (2012)
- The Three Stooges (2012)
- The SpongeBob Movie: Sponge Out of Water (2015)
- The Jungle Book (2016)
- Mother's Day (2016)
- Ice Age: Collision Course (2016)
- The Greatest Showman (2017)
- The Beach Bum (2019)
- Dora and the Lost City of Gold (2019) - with Germaine Franco
- Home Sweet Home Alone (2021)
- Luck (2022)
- 80 for Brady (2023)
- The Garfield Movie (2024)
- Horizon: An American Saga (2024)
- The SpongeBob Movie: Search for SquarePants (2025)
Debney also worked on these television projects:
- The Cape (1996) - we repeat - not this one, this was a 1996 series made for First-Run Syndication about astronauts. Winner of an Emmy Award for the score for The Pilotnote his theme nominated for an Emmy Award itself.
- Dink, the Little Dinosaur
- Disney's Wonderful World (theme arrangement)
- Doctor Who (Made-for-TV Movie) (1996)
- Dragon's Lair
- Jonny's Golden Quest (Made-for-TV Movie)
- Justice League of America
- The Halloween Tree
- The Lazarus Man (theme and score for the pilot)
- The Orville (14 episodes)
- The Pretender (first season theme; pilot score)
- A Pup Named Scooby-Doo
- Santa Clarita Diet (season 1; with Josh Debney)
- SeaQuest DSV Winner of an Emmy Award for Outstanding Individual Achievement in Main Title Theme Music. (theme and episode scores)
- Supah Ninjas (theme only)
- Texas Rising (a collaboration with Bruce Broughton)
- Tiny Toon Adventures: 2 episodes "Gang Busters" and "Hollywood Plucky".
- The Young Riders Winner of an Emmy Award for Outstanding Achievement in Music Composition for a Series (Dramatic Underscore) for the episode "Kansas".
- Young Sheldon (pilot score)