CAIRO  Iran’s government cannot silence the filmmakers.

It keeps trying. Films are censored. Directors are prohibited to leave the country and prohibited to return home, forced to cancel projects and threatened with punishment if their films are too probing or too critical of life in the Islamic Republic.

But the films keep coming, and so do the filmmakers.

Bahman Ghobadi’s latest work, “No One Knows About Persian Cats,” is banned in Iran but is being passed around for free, offering a searing portrait of life through the prism of a vibrant underground music scene. The movie has songs with lyrics like these: “This is Tehran, a city where everything you see entices you, entices your soul till you realize that you are not human, just trash.”

The film took the Jury’s Special Prize at the 2009 Cannes Film Festival, turning the red carpet of an international film festival into a platform to draw attention to the political crisis in Iran. Similar events occurred in Montreal, Berlin, Nuremberg, Mumbai and London, where Iranian filmmakers  by either their presence or their government-forced absence  have used their celebrity to keep the public focused on the turmoil that has roiled Iran since the presidential election in June, which opponents of the government have denounced as fraudulent.

“People of my country are killed, imprisoned, tortured and raped just for their votes,” Mohsen Makhmalbaf, one of Iran’s most renowned filmmakers, said after he accepted the Freedom to Create prize in London last month. “Every award I receive means an opportunity for me to echo their voices to the world, asking for democracy for Iran and peace for the world.”