Most of the movie is based on the graphic novels "Batman: Year One" and "Batman: Year Two". The flashback to Batman's first night of crime-fighting, donning a jacket and ski-hat is parallel to book one of "Year One". The design and concept of the Phantasm was derived from the Reaper, the primary villain of "Year Two".
The computer-generated version of Gotham City seen in the opening credits was originally designed to be used in the TV show. The purpose was to create a "virtual set" to replace hand-painted backgrounds and help speed up production of the series. It was never used for that purpose.
Andrea Beaumont is based loosely on a combination of Judson Caspian (the Reaper) and his daughter Rachel Caspian, characters from the "Batman: Year Two" comic book storyline. Andrea was allegedly named after casting and vocal supervisor Andrea Romano, whom star Kevin Conroy occasionally teased.
Late in production, Warner Bros. decided to make the movie a theatrical release instead of the originally intended direct-to-video feature. While the animators were thrilled and extremely grateful for this decision, this left them with less than a year of production time and scrambling to convert the aspect ratio to wide-screen.
One scene depicts Bruce Wayne at his parents' tombstone saying "I didn't count on being happy." According to writer Michael Reaves, this scene was to be a pivotal moment in Bruce's tragic life, as he, denies himself the opportunity to live a normal life. Reaves also stated, "When Bruce puts on the mask for the first time, [after Andrea breaks their engagement], and Alfred says 'My God!' he's reacting in horror, because he's watching this man he's helped raise from childhood, this man who has let the desire for vengeance and retribution consume his life, at last embrace the unspeakable."
When they reviewed this film for their show, Gene Siskel and Roger Ebert both said they regretted not seeing it in its theatrical release. Siskel in particular liked the film and compared it favorably to the other Batman films Batman Returns (1992) and Batman Forever (1995).
Kenner, which had already released toys for Batman: The Animated Series (1992), produced several tie-in figures for the film, including the Joker and the Phantasm (packaged unmasked, spoiling a pivotal plot point in the film)
Although the Joker does play a pivotal role in the film, it was Alan Burnett's intention to tell a story far removed from the television show's regular rogues gallery. Burnett also cited he "wanted to do a love story with Bruce because no one had really done it on the TV show. I wanted a story that got into his head."
Batman: The Animated Series: Trial (1994) was supposed to be the plot of this film. Producers thought it worked better as a standard half-hour episode. Some fans disagree, feeling that "Trial" is begging to be a two-parter.
The dummy corporations "O'Neil Funding Corp." and "Adams Tool and Die" shown on Batman's computer screen are references to Denny O'Neil and Neal Adams, respective writer and artist for Batman comics circa 1969. Their somber, camp-free stories have been called "ground-breaking" and are considered a major turning point for DC Comics' Batman titles, which O'Neil edits and oversees.
Many of the items featured at the Gotham World's Fair were inspired from items featured at the famous 1939 New York World's Fair. The rocket and planet centerpiece echo New York's famous Trylon and Perisphere exhibit.
The writers were highly cautious of placing the Joker in the film as they did not want any connection to Batman (1989), but writer Michael Reaves said, "We then realized that we could make his appearance serve the story in a way that we never could in live-action."
During a flashback, Bruce sees a model car at the Gotham World's Fair that resembles the future Batmobile. It is likely that he got this inspiration to later help Earl Cooper design the Batmobile as seen in -The Mechanic_.
The character of Arthur Reeves originated in the comics. In "Half-an-Evil", Reeves was a short-lived comic relief who had a bone to pick with the Batman. He ceased all complaints, and appearances, after the Batman frightened him senseless with one well-timed "Boo!"
In The New Batman Adventures: Beware the Creeper (1998), a TV special on the Joker shows him in an image during his earlier career with the Valestra mob. The image almost resembles the photo Batman finds of Carl Beaumont with the gangsters.
The construction site scene mirrors a similar sequence in Batman: Year One (2011), in which a rookie Batman is pursued into a tenement building by a crooked Gotham SWAT team, which Batman barely escapes.
Bruce Timm went through approximately 20 different character designs for the Phantasm before creating a version that resembles the Grim Reaper with Azrael's mask. The large blade on the right hand was not part of Timm's original design, and was added later at Alan Burnett's insistence.
As a visual joke, sequence director Kevin Altieri set the climax of the film inside a miniature automated model of Gotham City, where Batman and the Joker were giants. This was an homage to a mainstay of Batman comic books of the Dick Sprang era, often featuring the hero fighting against a backdrop of gigantic props (they would later do another homage to Sprang's works in The New Batman Adventures: Legends of the Dark Knight (1998)).
While the film was being written, [[Paul Dini,]] who was handling many of the Joker's scenes, was attacked and beaten by two muggers on La Peer drive, and had to undergo reconstructive surgery on his skull. He spent several months recuperating from the attack, physically and emotionally. As a result of the attack he almost backed out of the film, and even considered giving up working on Batman altogether before he returned to work on the script. He later wrote a graphic novel on his experience recovering titled "Dark Night - A True Batman Story."
Under the main headline "Mysterious Vigilante Repels Bandits . . . " on the newspaper Alfred is holding in the flashback sequence is the smaller headline "Radomski to Press: I'm Innocent!"--this is likely a reference to producer Eric Radomski.
Chuckie Sol's line when he tries to run over the Phantasm, "This time I've got you, you lousy stinking . . . " is almost exactly what was said by Tony Zucco in Batman: The Animated Series: Robin's Reckoning: Part I (1993), in which he almost runs Batman over, "Now I've got you, you lousy stinking . . . ".
In the World's Fair scene, shortly before Bruce remarks on the vehicle that looks eerily similar to his Batmobile, you can see a Billboard behind it reading "Turbine Power," a reference to Adam West's line from Batman (1966) when starting his Batmobile, "Turbines to power, engines to speed!"
The trivia items below may give away important plot points.
The fate of the Joker is left unrevealed in the movie, but The New Batman Adventures (1997) confirms that he survived Andrea's wrath: A DCAU comic expanding on the movie's events provides an explanation: Andrea drags him into the sewer below and they fight for a while until an explosion from above separates them and knocks Joker into the water, where he is carried away by the current.
The Phantasm would not reappear in DCAU continuity until Justice League Unlimited: Epilogue (2005), in which Amanda Waller tells the tale of an agent she hired to kill the parents of young Terry McGinnis. Though the assassin is never named, the silent depiction of the event clearly shows the Phantasm stalking the family. However, a visibly aged Andrea Beaumont refuses to complete the assignment, citing Batman's refusal to resort to murder to achieve his goals and how doing so would dishonor what he stood for.
Reeves confesses to Batman that he sold Beaumont out to the mob. This is the second time a character played by Hart Bochner sold out a fellow character and having it ultimately backfiring on him. The first time was Die Hard (1988), when his character Ellis tries to sell out John McClaine to the terrorists; his failed efforts ultimately get him killed.