Inside: A Chinese Horror Story (2017)

Cui Kai is a has-been writer and lives in his distressed apartment, unemployed. One day he receives an exciting job offer from an editor-to create a horror series. Kai has finally completed the horror series. The book becomes an immediate hit. However, fame does not make Kai any happier. Every story in his book is inextricably intertwined with his own life. He himself has a personality split and the obese man is in fact his other self that he is afraid of. Kai is able to eventually defeat his dark side and obtain a complete and wholesome personality. All the characters Cui Kai created are the split personalities of himself during his time in the asylum.

Unfortunately the movie Inside: A Chinese Horror Story is not yet available on HBO Max.