Coulais met François Reichenbach, who asked him in 1977 to sonorize his documentary México mágico who permit to compose the first soundtracks for Jacques Davila "qui trop embrasse" en 1986 .

In 1994, he met the television producer Josée Dayan, who let him write a theme for the TV series La rivière esperance, aired on the France 2 network in autumn 1995.

His reputation was confirmed by the soundtracks to Himalaya (1999) and Les rivières pourpres (2000), and after that Bruno Coulais's name was to be found on most new French blockbusters, such as Belphégor and Vidocq.

The same year, he wrote the soundtrack to the film Les choristes by Christophe Barratier, starring Jean-Baptiste Maunier in the lead soprano singing role, which subsequently became an international hit.

Since then, Coulais's collaborations in cinema seem to be limited to works by directors with whom he already shares some history, in particular Jacques Perrin, Frédéric Schoendoerffer, and James Huth.