In 1977 a mentally retarded woman was traveling from Bangkok to Uttaradit near Chiang Mai by train without a ticket and was thrown off the train somewhere near Phitsanulok in central Thailand. The next day she was gang raped and murdered to shut her mouth... who was responsible for this? This film is about the police investigation into this case which is 100% true and was eventually solved.
Unfortunately the movie The Macabre Case of Prompiram is not yet available on HBO Max.
| Directing | Manop Udomdej | Director |
| Writing | Manop Udomdej | Writer |
| Production | Kunakorn Sethi | Producer |
| Production | Somsak Techaratanaprasert | Executive Producer |
| Production | Kamla Yukol | Executive Producer |
| Sound | Richard Harvey | Music |
| Sound | Sandy McLelland | Music |
| Crew | Anuparb Buachan | Cinematography |
| Editing | Patamanadda Yukol | Editor |
| Sound | Michael Pärt | Sound |
| Sound | Michael Pärt | Music Editor |
