China's State Administration of Radio Film and Television has issues new guidelines for filmmakers which include some unexpected items. Its assertion that films must contain positive thinking and must avoid ambiguous morals is understandable coming from a regime which takes a hands-on approach to social cohesion, though it would exclude some of the most interesting Chinese films of recent years. But its ban on time travel has really raised eyebrows.
The thinking seems to be this - China is proud of its history, therefore stories in which history is altered are unpatriotic. It also advises against fantasy and the mingling of different myths, which seems to be an attempt to preserve the country's legends intact, though any scholar will tell you that it is in the nature of legends to evolve over time. Assorted superstitions, including belief in in reincarnation, are ruled out as the country tries to dissuade its people from holding on to old ways of thinking in the modern age.
The State Administration of Radio Film and Television has not directly prohibited the filming of stories which break these rules, but as most Chinese filmmakers rely heavily on state subsidy it is unlikely they would be able to go ahead without its approval. There is also an atmosphere of caution within the creative community after the arrests of several prominent filmmakers and artists said to have betrayed their country.