Soylent Green is a 1973 dystopian police procedural science fiction movie directed by Richard Fleischer and starring Charlton Heston.
Soylent Green is set in a future time (The year 2022) where the world has been ravished by Greenhouse gasses, pollution, and is experiencing an overpopulation problem.
When a man working for the Soylent Corporation is murdered, Detective Frank Thorn (Charlton Heston) is tasked with solving the case. What he uncovers during his investigation is a shocking revelation about how Soylent Green is actually being produced.
Soylent Green is not transhumanist in itself, it focuses heavily on overpopulation, a point of debate among many in regards to both life extension and transhumanism.
It is also a great example of science fiction as a piece of social commentary on the time during which it was created.