In 1999, having always assumed he was the only child of a cook and a housemaid, Jackie was surprised to learn that not only was he just one of numerous siblings, but also that his kung-fu fighting father had a previous life as a Shanghai gangster - then as a hit-man for statesman and Chinese Nationalist leader Chiang Kai-shek.
His mother, meanwhile, whose failing health precipitated his father's belated confessions, had been an opium dealer known locally as the 'Third Sister', whose idea of fun was striding into a casino with a horse whip.
The product of a Brady Bunch-style marriage between these two extreme personalities, Jackie was separated from his parents aged eight after they emigrated to Australia, spending the next 10 years in a Peking Opera school. So his shock and bemusement as the irascible rogue relates these tales is genuine, particularly when Fang describes his narrowly-avoided decapitation by the Japanese ("They cut off nine heads! The neck shrunk into the body!"), accompanied by graphic stills.
The film's narrative often becomes overwhelming, as it encompasses decades of political upheaval caused by the Sino-Japanese War, World War II and the Cultural Revolution, during which entire families were torn apart. But the emotive moments as the disbelieving star comes to grips with his heritage render the historical immensely personal. This is especially true in the final scenes, as Fang hunkers down among his sons and their relatives for a long-overdue family portrait. An old man finally at peace.