Trivia: This movie is based on the book "Flowers for Algernon." The Simpsons also spoofed this in an episode called "HOMR." (The one where they find that Homer has a crayon up his nose.).
Charly (1968)
1 trivia entry
Directed by: Ralph Nelson
Starring: Cliff Robertson, Claire Bloom, Lilia Skala, Leon Janney
Revealing mistake: Whenever Dr. Nemur is smoking, you can tell the cigarette's not lit, because you can't see any smoke. When Mrs. Kinnian smokes in the movie, plenty of smoke is visible.
Charly Gordon: That, that is, is. That, that is not, is not. Is that it? It is.