In 1937, Japanese troops invaded Nanjing – slaughtering civilians, burning the city and trying to erase the evidence. A few brave Chinese risked everything to hide photographs of these atrocities, which later helped convict the perpetrators.

Eighty years after WWII, only 27 survivors of the Nanjing Massacre remain. Dead to Rights brings their truth to the big screen – and this video explains why we can't let the story fade.