Holmes began his career in a comedy double-act, The Gruber Brothers, with Stefan Schwartz.
He went on to co-write and produce Shooting Fish (1997) starring Kate Beckinsale, Stuart Townsend and Dan Futterman.
In 2008 he produced, alongside Christian Colson, the critically acclaimed feature film Eden Lake (2008), written and directed by James Watkins.
From 2013 to 2016 he worked at Creative England and executive produced 45 Years which won multiple awards for Andrew Haigh and actors Charlotte Rampling and Tom Courtenay.
He also executive produced The Ecstasy of Wilko Johnson, Orion: The Man Who Would Be King, Notes On Blindness, God's Own Country, Calibre and The Girl with All the Gifts.