He studied at the CNSAD and began his acting career in his native France in 1990. This was followed by a leading role in Jean-Paul Rappeneau period film The Horseman on the Roof (Le Hussard sur le Toit) in 1995 in which he starred alongside Juliette Binoche as an Italian nobleman. The film was hailed as the most expensive French film at that time in history but failed to reach its $35 million budget. Martinex portrays a French foundry worker who wins a strongman contest and the its prize of a trip to Southampton to see the launch of the Titanic.
