'The Interrupters': Documentary On Youth Crime Spotlights Ex-Gang Members Who Try To Prevent Violence

Watch The Interrupters Preview on PBS. See more from FRONTLINE.

A growing school of thought holds that street violence is a disease, and like a disease, it can be prevented.

That's the central premise of Ceasefire, a Chicago group that aims to mediate and pre-empt conflicts before they have the capacity to become violent. Ceasefire is the focus of "The Interrupters," a documentary that will air on PBS's "Frontline" tonight. (The film was directed by Steve James, who also created the acclaimed 1994 documentary "Hoop Dreams.")

The violence interrupters — who have amassed consider street cred as former gang members themselves — often place themselves in serious danger when stepping into disputes. The young people they work with are especially at risk: In 2010, nearly 700 people under the age of 18 were struck by gunfire. Sixty-six of those children died.

One of the most compelling figures in "The Interrupters" is Ameena Matthews, a former gang enforcer and the daughter of Jeff Fort, the founder of the powerful, ruthless Black Stone Nation gang. (Fort is serving consecutive life sentences for planning domestic terrorism and for ordering the murder of a rival.) Ameenah is now one of the program's interrupters, and stands out both for her Muslim attire and for her charisma.

Watch her being interviewed by Stephen Colbert: