"It's a lasting regret of mine that he wasn't around to see the finished film, but I'm happy at least that his story has been told."
Director Justin Chadwick is lamenting the loss of Kimani Maruge, a veteran Kenyan farmer whose personal history he has turned into an African epic of a film.
The First Grader, which has already won numerous festival awards around the world, tells how, when Maruge heard on the radio in 2003 that his government were offering free education for all, he knocked on the door of the local primary school and demanded to take his place next to the six-year-olds - despite being in his eighties at the time.
By the time the film-script came to Chadwick, whose previous projects include The Other Boleyn Girl on the big screen and the hit BBC drama Bleak House, Maruge, played by Oliver Litondo with Naomie Harris as his indefatigable teacher, was already a totem of optimism in his own country - appearing on posters for Kenya's education system, and travelling to speak at the United Nations in New York.
But when Chadwick arrived in Kenya to meet his film subject and launch into pre-production, it was clear that Maruge was already very frail.
"He was happy for me to tell his story," remembers Chadwick. "I met with him many times before we began the shoot. He was 89, very ill, but he still had teachers visiting him, and by the time he died had reached Grade 5. He was absolutely determined never to stop learning."
"Sadly, he died three weeks before we began shooting the film. We had planned for him to make an on-screen appearance, but sadly it was not to be."
Although Maruge's story is ultimately a victory, the film doesn't flinch from depicting his brutalised past - having his land taken from him, his family killed before his eyes, and then eight years of incarceration and torture because of his part in the Mau Mau Uprising - all at the hands of his pro-British-rule oppressors.
For British Chadwick, this meant working in Kenya and sitting down with men who had every reason to view him with total hatred and distrust.
"There was a lot of forgiveness," he explains. "I moved production completely to Kenya, and made it very clear I wanted to work with locals and tell their story the way they wanted. And they responded.
"Every incident in the film is true, because it's based on first-hand accounts, that some of the crew, even though they were local, had never heard before. So they had to go away and delve into their history with their families."
Chadwick has come away with a fresh respect both for the African community - including dozens of real-life schoolchildren at the heart of the film - and for the British education system with all its privileges.
"These children had never seen a film or a TV screen," says Chadwick.
"When I filmed them, I had to present it to them as a school lesson. And when I left, they always wanted more. They were hungry to learn, to read. As troubled as our own education system is, it's humbling to realise just what we have and how precious it is."
WATCH the trailer for The First Grader here:
The First Grader is a BBC Films/UK Film Council production and is now on release. For more information, visit The First Grader website