When he was about twenty years of age, Michel Janvier made his first comics for the fanzines La Claque and L'Abcès. Later on he specialized in photography and illustration. He did most of his illustration work in the advertising field, such as for the Michelin Guides. From 1982 Janvier worked regularly for Dargaud publishers. In 1986 he cooperated on the 'Lucky Luke' album, 'Le Ranch Maudit', which contained short stories written by Claude Guylouis, Jean Léturgie and Xavier Fauche.
A year later, Morris decided to start a spin-off series with the stupid dog 'Ran-Tan-Plan', one of the most popular 'Lucky Luke' characters. Janvier did the artwork on six albums until 1997. From 1998 Janvier cooperated with Véronique Brissaud and Gilles Ratier on 'Bédé Philes', a section about comics in L'Écho du Centre. The same year, he created 'L'Histoire de la Porcelaine en Bande Dessinée' and the characters 'Rob, Wed & Co'. The latter began as a series of self-published albums, but the series later appeared at Bamboo under the name 'Les Musicos', scripted by Erroc and Jenfèvre.