How did this movie get into cinemas?

Niu Lai, the Chinese animated film that went viral for its animation style, was made by a mother and son with no film crew, no budget, and no marketing. It made almost nothing in its first ten days. Then it became one of the most profitable movies ever made. I trace how Niu Lai actually got made and how it ended up in Chinese cinemas, from Xin Yumeng and Sun Lifang teaching themselves animation and screenwriting from scratch, to a release with zero marketing and one poster, to the film going from 7,169 yuan in ten days to tens of millions after Chinese social media turned its rough animation into a viral joke. For breakdowns of how people actually get their start, in the same vein as Johnny Harris or Magnates Media, this is for you.