On January 7, 2015, two terrorists stormed the offices of satirical magazine Charlie Hebdo in central Paris and murdered ten of its employees, including legendary cartoonists Cabu, Wolinski, Charb, Tignous and Honoré. Ten more workers were injured, two policemen arriving at the scene were also slain, and freedom of expression – a core value of French democracy – was dealt a heavy blow. Over the next two days, eight more people were murdered in four other incidents in Paris, including an attack on a kosher supermarket. This documentary by father and son Daniel and Emmanuel Leconte revisits those fateful days, providing historical background and incorporating exclusive interviews with survivors of the attack.