The Oscar-nominated documentary Cartel Land from filmmaker Matthew Heineman began as a cinematic portrait of the American vigilantes bent on curbing the flow of Mexican drug activity into their state of Arizona. But when Heineman learned of the Autodefensas, a civilian group waging its own war against the cartels in Mexico, he took his camera south of the border. Bob talks to Heineman about how his film blurs the line between good and evil, and how he was able to capture extraordinary moments of violence, corruption, cult of personality and even adultery, all with his subjects’ full participation.