Max Rowlandson, 10, on the set of Maximus, a short film that tells his inspiring story of overcoming cancer.

Many of the best fantasy stories have some seed in the real lives of their creators. The Narnia books, for instance, came out of author C. S. Lewis’s devout Christian faith. And when his friend J. R. R. Tolkien was writing The Lord of the Rings, an epic saga about an ultimate battle between good and evil, Tolkien was likely channeling his experiences as an officer in World War I. Harry Potter probably never would have been created if J. K. Rowling’s older brother hadn’t once crayoned a lightning bolt on her forehead. (Full disclosure: one of these three examples isn’t true.)

That brings us to a new 15-minute film full of flashing swords and supernatural creatures that has its origins in a very personal story: a young British boy’s near-fatal illness. Today, Max Rowlandson is a healthy 13-year-old, but when he was only two he was diagnosed with leukemia, a deadly cancer that affects the cells in bone marrow and blood.