This documentary debuts Monday, September 19, 8 – 9 pm ET/PT, on HBO. Check HBO and HBO2 listings for other playdays in September and October.

On January 7, 2015, two brothers who claimed allegiance to Al-Qaeda in Yemen entered the Paris offices of the satiric weekly Charlie Hebdo, murdering 11 people and injuring 11 others before killing a French police officer. While a manhunt was underway for these terrorists, a third gunman claiming allegiance to ISIS shot a police officer before taking hostages at a kosher supermarket. In a recording, this terrorist said of the two events: "They attacked Charlie Hebdo . . . while I took on the police. So there you go. We acted kind of together, kind of separately . . . to have more impact."

Making great use of exclusive access to hostages, survivors, police, paramilitary forces, and intelligence activities, as well as never-before-seen footage and photographs, this HBO documentary of the three-day terrorist campaign of death and destruction in Paris immerses us in the shock, the violence, the heroism, the grief, and the teamwork of those seeking to bring an end to the bloody siege.

Three Days of Terror: The Charlie Hebdo Attacks is written, directed and produced by Dan Reed who orchestrates the events with a keen sense of the helplessness of the victims, the ruthlessness of the terrorists, and the patience and professionalism of the police and other agencies involved in the search for the gunmen. In celebration of their mission to murder journalists at Charlie Hebdo, the first two terrorists scream out on the street: "We have avenged the prophet Mohammad!"

Perhaps the most telling comment on the entire siege is given by Professor Pierre Tourtier, Chief Medic of the Paris Fire Brigade:

"Yes, the terrorists will risk their lives for their ideas. But there are many French people — medics, firefighters, gendarmes, policemen, ordinary citizens — who are also ready to risk their lives for their ideas."