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Michael Keaton and Matthew Modine have appeared separately in Batman and The Dark Knight movies: Keaton as the title character in Batman (1989) and Batman Returns (1992), and Modine as a cop in The Dark Knight Rises (2012).
Screenwriter Daniel Pyne once rented an apartment to a tenant that he could not evict. The film was inspired from this scenario.
The home of Melanie Griffith and Matthew Modine's characters is not in Pacific Heights at all, but right across town in San Francisco's Potrero Hill district at the corner of Texas Street and 19th Street.
In the original script, Carter (Michael Keaton) was a bisexual man who sexually threatens Drake (Matthew Modine) and Patty (Melanie Griffith).
Christopher Reeve unsuccessfully lobbied John Schlesinger personally for the "Carter Hayes" role.
Melanie Griffith didn't like the experience of filming this movie, and made some complaints about it while she was filming The Bonfire of the Vanities (1990), which started filming a few days after this film had been completed.