There are a lot of small factors that could have changed the face of Batman: The Animated Series.

It was lucky to have a foreign animation studio skillful enough to airbrush the gloss on to every frame of Mr. Freeze’s helmet. It was lucky to have the talents of freelance casting director Andrea Romano, who, if you are in a certain age range, is responsible for the voice of nearly every cartoon character that formed the basis of your childhood. Batman: TAS was lucky to have convinced nervous censors that it was vital that Batman face off against criminals wielding real guns that fired real bullets and not the laser weapons of G.I. Joe and other action cartoons that had gone before it.

But as much as any other behind-the-scenes element on the show, Batman: The Animated Series would have felt significantly different — maybe even unrecognizable — without Shirley Walker.

BAAH DAAH DAH-DAAAHH

Had Batman: The Animated Series been made at a production studio other than Warner Bros., it probably would have been scored with stock cues from a music library. In that era, Warner Bros. set a high standard for even its half-hour animated television series — full scores of original music recorded by a real orchestra. And for Batman, that music was largely written and that orchestra was largely conducted by a composer whose career was based in feature film.

Shirley Walker was the first American woman to be the sole composer on a major studio release. And in a profession dominated by men, she often found work assisting other film composers with her skills as a conductor and orchestrator. She was a frequent contributor to John Carpenter’s films, and often collaborated with Hans Zimmer and Danny Elfman, on A League of Their Own, Scrooged, Dick Tracy and, of course, 1989’s Batman.

But it was her work on another Elfman project, 1990’s The Flash TV show, that brought her to the attention of Batman: The Animated Series’ co-creator Bruce Timm. Still, she was initially reluctant to come on to the production.

“Though Shirley had enjoyed her stint composing for [The Flash],” notes Batman Animated, an art-book and history of the show, “she thought the last thing she wanted to do was to work on a cartoon version of Batman.”

Still, she met with producers, and was so impressed with the direction of the show’s art and the intended depth of its characters that she agreed to come onboard. Her relationship with Danny Elfman facilitated the use of that film’s music in the series, though Walker also composed her own equally memorable theme. You can hear her explain the difference between the two pieces of music, the tonal sections of her Batman theme and how she would blend them together to map over the show’s various moods and scenes, in this track from the soundtrack album:

It was Walker and the rest of her composing team who furnished a Saturday morning kids’ cartoon with a full suite of character-specific musical themes, just as composers like John Williams and Howard Shore have done franchises as big as Star Wars and the Lord of the Rings. Walker based her music on a combination of design, mannerism and even character voice, once an actor for the part had been chosen and their final personality had been made clear.

Here, you can hear Batman and the Joker’s leitmotifs duke it out even as their characters do. Two-Face’s is a haunting song of his tragic backstory, and Catwoman’s is low, furtive and nimble. Mr. Freeze’s is a waltz of bells that perfectly evokes the ballerina snow globe that he keeps in memory of his wife.

She would go on to work on Superman: The Animated Series and Batman Beyond, setting the musical, well, tone for the slew of DC Animated Universe shows that spun out of Batman: TAS — an interconnected cinematic universe including Static Shock, Justice League and Justice League Unlimited.

Walker died in 2006 of complications from a stroke, at the early age of 61. By that time, she had scored more Hollywood productions than any other female American composer. Yet, that year, she was omitted from the “In Memoriam” segment of the 79th Academy Awards due to time constraints.

So, on the 25th anniversary of Batman: The Animated Series, take a moment to remember Shirley Walker. We might not have ever seen her, but we’ve been hearing her for a quarter of a century. Hopefully we will for quite a few years more.