Aziz in City of Ghosts (Amazon Studios/IFC Films/A&E Indie Films)

Since the declaration of the ISIS caliphate in 2014, there have been only two sources for on-the-street footage from Raqqa, Syria, available to outsiders: the propaganda videos that ISIS posts vs. the truth beamed out to the world by the citizen journalists collective Raqqa is Being Slaughtered Silently (RBSS). Director Matthew Heineman admired the risks RBSS took to capture the violence and deprivations forced on the city’s residents, scenes of which recall his experience on the frontlines of the Mexican drug war in Cartel Land (2015) along the U.S./Mexico border. In City of Ghosts, he caught up with the young RBSS founders as they fled for their lives to Turkey and Germany in 2015 and profiles their work and adjustment to exile.

The three founders—Aziz, 25 years old; Hamoud, 23; and 27-years-old Hussam—along with married reporter Mohamad, 34, say they weren’t political until the Arab Spring that blew through Syria as a revolution began against the 40-year rule of the Assad regime in 2012. They each began posting footage from demonstrations on Facebook. The urbane city’s population of more than 200,000 swelled with refugees from other cities, fighters from the Syrian Free Army, and other rebel forces.

But gradually, ISIS fighters, with their distinctive black flags, arrived in the city to proselytize, backed up by heavy military might, and many rebel fighters started switching allegiance. Through 2013, ISIS built up its numbers and attacks on other forces. By 2014, ISIS controlled the city and its propaganda media geared up, with its leader declaring the reinstitution of the historic caliphate, with Raqqa as its capital, the only Islamic extremist group with an ancient homeland. Kurds, Christians, and the Alewites (the Assad family’s ethnic group) were forcibly removed (and worse), and outward evidence of piety began to be enforced. Out went the call for Muslims internationally to support the Islamic paradise, and they came.

It was, in fact, no paradise. Until July 2014, the outside world had no visual evidence of what was happening from the highly restricted area. Passionate that “ISIS is not Islam,” RBSS organized, from its members’ own pockets, to send out to the global media dramatic images, such as executions in the streets, bodies lying in the streets, and beheadings in the town square as the religious rules get stricter. The early distributions of bread became restricted to ISIS fighters, and RBSS filmed the lines of starving, bedraggled children begging for food handouts, who become susceptible targets for the secretly filmed training camps that resemble those for African child soldiers.

All of RBSS’s reporting was a completely forbidden activity, and ISIS hunted the group and many are killed. Hamoud tearfully tells of the price his father and younger brother paid. The four men manage to flee Syria, even as they somewhere still have underground reporters who provide them footage through the latest in encrypted software now that the group has outside funding.

ISIS continues to proclaim them enemies, so now when police come to Aziz’s Berlin apartment it’s to warn him of a new threat and the promise of extra security. When asked how the four handle this stress, there’s a shrugged response: “We’re used to threats. We change houses a lot.” As they huddle together conferring on newly received footage and what’s appropriate to post on their web and Facebook pages, they chain smoke. All are homesick; just the sight of the Syrian flag makes them teary. Heineman asks off camera: “Is there any hope in Raqqa?” They all shake their heads no.

In late 2015, one representative travels to New York to accept an International Press Freedom Award from the Committee to Protect Journalists. Returning to Germany, he and the others find themselves surrounded by anti-immigrant demonstrations. They wonder if Germany is safe and watch the TV news of ISIS-inspired terrorist attacks in France. Then they urgently go back to their phones and laptops to upload new footage. The onslaught by anti-ISIS forces on their beloved hometown only discourages them about dispersal of the fanatics and the neighborhood by neighborhood destruction for the 100,000 or so civilians still there.

Other documentaries about the Syrian conflict feature interviews with traumatized civilian refugees from Raqqa about the tough life under ISIS control, but they all depend on RBSS footage for their visual support. City of Ghosts not only has the most of its footage, some of which hasn’t been seen before, but the founders’ narration of the risks taken to bring out those startling images adds an important layer of understanding to the assault that’s going on now to ferret out holed-up ISIS fighters. The UN warns, “The humanitarian situation in Al-Raqqa remains dire,” and RBSS is now reporting air strikes have killed significant numbers of civilians.