Born in Montréal, Québec, Canada, Baillargeon worked as composer, conductor, and music arranger since 1970 with credits such as the drama Love in a 4 Letter World (1970), the comedy Loving and Laughing (1971), the comedy Keep It in the Family (1973), the television series The Big Blue Marble (1977) and Curious George (1980), the comedy Les chiens chauds (1980), the drama Yesterday (1981), the television drama The Brass Ring (1983), the drama Somewhere, Tomorrow (1983), the science fiction film Anna to the Infinite Power (1983, directed by Robert Wiemer) in which he also had a cameo part, the television drama The Night Train to Kathmandu (1988, with Kavi Raz), and the mini series Piège infernal (1989) and La misère des riches (1989).