Almost six years ago, my friend Steven Schwankert came to me and suggested that we make a documentary about the Chinese survivors of Titanic. “There were Chinese people on Titanic?!” was my immediate reaction. It’s a sentence I’ve heard a lot in the years since, pretty much every time we have told people about the film we are working on. And it is the fact that no one seemed to know about the Chinese on board the most famous shipwreck of all time that spurred us on to finish what at times seemed like an impossible task.

There were more than 700 survivors of Titanic, and almost all of them are well known, at least in their country of origin. When I was a child, we lived opposite the house of an elderly woman who had survived Titanic. Everyone knew about her. If you check online now, you can find her year of birth, her children, the story of her life, her story on Titanic. And the same is true of all the other survivors. Except our six men.

So, why were the Chinese so uniquely forgotten by history? Why had no one come forward to claim them as grandparents, uncles, or even friends?

The more we looked, the more we suspected it had something to do with the rumours published in British and American media in 1912 that implied the six men had acted dishonourably to save themselves. But were those terrible accusations – that they had dressed as women to get places on lifeboats, that they had hidden, or were stowaways – have something to do with the discrimination that an entire generation of Chinese faced as they went out into the world to work, and settle? The story just seemed to get bigger and bigger, and the task of sorting out fact from fiction at times seemed insurmountable.

Fortunately, Steven and I were joined along the way by an incredible team of collaborators, including our Chinese and international researchers, spread out over China, the US, the UK and Canada, our amazing production team at LP Films, and – just when we really needed his help – James Cameron.

Being involved in The Six has been the privilege of a lifetime. And I will never be able to thank enough the people we met along the way – above all the descendants and relatives of the survivors who helped us to tell this story for the first time. I hope that this film is a fitting tribute to a whole generation of Chinese whose suffering lasted a lifetime and who faced discrimination that we have only really begun to reckon with as a society in the last year or so.