Intouchables (known as Untouchable in the UK) is the most successful French-language film ever made. And just as the previous title-holder, Amélie, turned Audrey Tautou into an international star, so Intouchables is having the same effect on Omar Sy. But where Tautou, gamine and Gallic, belongs to a highly bankable tradition, Sy is a one-off, at least for now. He's the country's first black superstar.

The fourth of eight children raised in the banlieue by Senegalese Mauritian parents, the 35-year-old is France's darling: as well as winning best actor at the 2011 Césars, he was voted the nation's most popular person in a poll for Le Journal du Dimanche. A hefty share of the $269m raked in by Intouchables must be attributable to his smile.

It helps that there is some overlap between Sy's rags-to-riches story and the plot of his breakthrough film. In Intouchables, a buddy movie in which the buddies cross the divides of age, class, race and mobility, Sy plays a street tough who lands a job caring for a paraplegic billionaire. In the process, he transforms not only his own prospects but the lives of a supporting cast of upper-class stiffs.

Sy recently moved to Los Angeles, though he insists he will continue to pay taxes in France, perhaps wary of following too closely in Gérard Depardieu's footsteps. He now has a slate of US movies lined up, including superhero blockbuster X-Men: Days Of Future Past, in which he will star alongside Michael Fassbender and Jennifer Lawrence.