Harry Gregson-Williams (born December 13, 1961) is an English composer, orchestrator, conductor and music producer who provided additional soundtrack music for the 2012 film Prometheus, although he was not credited for this work. He was also originally hired to compose the soundtrack for the 2017 film Alien: Covenant, but was eventually replaced by Jed Kurzel.
- Gregson-Williams' work on Alien: Covenant will make him only the second composer to work on more than one film in the Alien, Predator and Alien vs. Predator franchises, after Alan Silvestri (who composed the scores for Predator and Predator 2).
- Although he was not listed in the credits of Prometheus for his contributions to the film, Gregson-Williams was credited for the music he composed on the film's soundtrack release.