His first screen appearance was in 1997, when he played a young gay beur in the short film Les Corps ouverts, directed by Sébastien Lifshitz.

Other notable films in which Belmadi appeared include Les Amants criminels, Wild Side, Beur blanc rouge and Grande École.

Adieu Gary went on general release in France on 22 July 2009, four days after Belmadi's death.

Belmadi's last rôle was in Pigalle, a production for French television channel Canal+, which he completed on 17 July 2009.

On 18 July 2009, at 6 a.m., the scooter which Belmadi was riding collided with a lamp post at the intersection of the Pont de Sully and the Boulevard Henri IV in Paris.