Telling the story of hematologist Franco Mandelli means turning the light on in a dark room. The light is loving and curative, yet blazes boldly in the face of obstructionism and inaction. The documentary, directed by Giancarlo Rolandi, does so through the letters of one of Mandelli’s patients, Vanessa, a young girl who would lose her fight against leukemia. And that is just when Mandelli named a facility, La Residenza, after her; since 1994, in via Forlì, in Rome, it has welcomed 4,600 patients and their families, free of charge.