Winner of both a BAFTA and an Academy Award for its screenplay, Chinatown is widely taught in film schools as an example of how to write a near-perfect script. But as well-made as the screenplay may be, Roman Polanski's role as director led to significant changes to the original—so significant that producer Robert Evans said Polanski and screenwriter Robert Towne were not on speaking terms by the end of the project.
One hundred and seventy-eight pages long, the first draft of Chinatown took Robert Towne nine months to finish. Evans called it brilliant but noted its incomprehensibility. Towne has said that, if shot from the first draft, the film would have been a mess. While the changes Polanski made are few, the impact of those changes was great.
One detail Polanski insisted on was that the characters physically go to Chinatown, a place that in the original script was only alluded to. Another significant change came with Evelyn's confession: early in the production, when Towne and Polanski were still communicating, Towne went to the director and admitted he couldn't figure out a convincing way for Evelyn to reveal her shameful secret about Katherine's identity. Towne realized it was going to be perhaps the most memorable scene in the film, but he didn't how Jake should induce Evelyn to make the emotionally shattering confession. Polanski's simple but brutal answer to Towne’s predicament was to have Jake slap her as she gets the words out.
This violent solution is suggestive of the overall darker vision Polanski had for Chinatown—particularly its ending. In his original conception, Towne wrote into the script a sense of justice with Evelyn killing her father and escaping with her daughter. Polanski preferred a tragic ending in the mold of Steinbeck's Of Mice and Men. The night before the shoot, Polanski—having fallen out with Towne—rewrote the final scene himself. Polanski has said that Towne later agreed with his tragic approach to the ending, which Polanski believes is among the main reasons the film garnered the legacy it has.
