Desplat has extensively composed for films, first in France and later in Hollywood, including scores and incidental music for some 100 films among which are Lapse of Memory and Family Express (both 1992), Regarde Les Hommes Tomber (1994), Les Péchés Mortels (1995), the César nominated Un Héros Très Discret (1996), Une Minute De Silence and Sweet Revenge (both 1998), Le Château Des Singes (1999), Home Sweet Home and Reines D'Un Jour (both 2001), the César nominated Sur Mes Lèvres (2002), and Rire Et Châtiment (2003), among others.
Desplat has composed individual songs that have been sung in films by artists such as Akhenaton, Kate Beckinsale, Charlotte Gainsbourg, Valérie Lemercier, Miosotis, and Catherine Ringer. He has also written music for the theatre, including pieces performed at the Comédie Française. Desplat has conducted performances of his music played by the London Symphony Orchestra, the Royal Philharmonic Orchestra, and the Munich Symphony Orchestra. In addition to his composing and performing, Desplat has also given Master Classes at La Sorbonne in Paris and at London's Royal College of Music.
In 2007 he composed the high profile scores for Philip Pullman's The Golden Compass; Zach Helm's directorial debut Mr. Magorium's Wonder Emporium with American composer Aaron Zigman; and the Ang Lee movie Lust, Caution. Prior to these breakout works, he contributed scores for The Luzhin Defence, Girl with a Pearl Earring, Syriana, Birth, Hostage, Casanova, The Nest and The Painted Veil, for which he won the Golden Globe Award for Best Original Score, Los Angeles Film Critics Association Award for Best Music, and the 2006 World Soundtrack Award. He won the 2007 BMI Film Music Award, 2007 World Soundtrack Award, 2007 European Film Award, and received his first Academy Award nomination for Best Original Score for The Queen. He also won the Silver Berlin Bear at the Berlin Film Festival for Best Film Music in The Beat that My Heart Skipped. In 2008, Desplat received his second Oscar nomination for David Fincher's The Curious Case of Benjamin Button.
Desplat's recent projects include Largo Winch, based on the Belgian comic; Afterwards a French-Canadian psychological thriller film directed by Gilles Bourdos in English; Anne Fontaine's Coco avant Chanel based on the life of designer Coco Chanel; Robert Guédiguian's L'Armée du Crime; Cheri, reuniting him with director Stephen Frears, whom he collaborated with on The Queen; Un Prophète reuniting with director Jacques Audiard; Julie & Julia directed by Nora Ephron; Fantastic Mr. Fox, directed by Wes Anderson and based on the novel by Roald Dahl; and New Moon, directed by Chris Weitz, out in November 2009.
Desplat's upcoming projects are The Tree of Life, directed by Terrence Malick, The Ghost, directed by Roman Polanski, and Largo Winch 2 .