A documentary about Lisbon Maru, a Japanese cargo ship that sank in the East China Sea during World War II, is soon to be screened to the public. Over 1,000 British prisoners of war were on board at the time, when a group of Chinese fisherfolk managed to save hundreds of them. CGTN Reporter Cao Chufeng caught up with the director and the historical advisor for the film to learn about what inspired them to dedicate eight long years to the project.