Supergirl appears on Superman: The Animated Series and Justice League Unlimited as Kara In-Ze, the last survivor of Krypton’s sister planet Argos. When Argos was throw out of its orbit by Krypton’s explosion, Kara’s mother Kala In-ze, the planet’s top scientist, constructed cryogenic chambers in an attempt to save her family before Argos became inhospitable to life. Tragically only Kara survived the process. Upon being brought to Earth by Superman, she fashioned a Supergirl outfit for herself and set upon working with her “cousin” to help the people of Earth as she could not help the people of Argos.
Supergirl shares all of Superman’s powers, and has a greater resistance to Kryptonite due to being Argosian. She adopts the name “Kara Kent” as her secret identity and wears glasses and a brunette wig as a disguise.
Supergirl’s costume features some unique elements not previously found in Supergirl costumes, such as a white cropped t-shirt, gloves, and shorter lace-up boots. This costume appeared in the comics when Linda Danvers crafted her Supergirl costume in SUPERGIRL #51 (2000). In the final season of Justice League Unlimited, when Kara has aged to around 20 years old (2), she creates a new costume that is closer to the traditional blue-and-red Supergirl costume.
Supergirl joins the expanded roster of the Justice League in the opening episode of Justice League Unlimited. In the last season she is taken to the 31st century where she meets the Legion of Super-Heroes. Feeling more at home with that era’s advanced technology and her new friends in the Legion, she decides to remain there permanently.
Differences from DC Universe comics
The creators of Superman: The Animated Series originally intended to use the original Kryptonian version of Supergirl from the Silver Age. However, at that time, DC Comics company policy mandated that Superman be the sole survivor of Krypton. The show’s creators got around this in a very clever way: in the series Argo City became a planet named Argos that had been settled by Kryptonians. Technically Kara was not Superman’s cousin when she was introduced in the Superman series, but she was treated by the other characters in a familial way. By the time of Justice League Unlimited, the DC Comics ban on Supergirl being Superman’s cousin had been lifted, and she is referenced in JLU as being his cousin.
Paul Dini, one of the series’ creators, explains:
We wanted to do the original version, which is Superman’s cousin from Krypton; [however], we ran into a wall with DC because they insisted that Superman be the last Kryptonian. So we did a compromise: she’s from a small planet in the neighboring system that was colonized by Kryptonians, but they’ve evolved slightly differently.”
“She’s sort of a cousin, in terms of being from pretty much the same race and, when she shows up on Earth, she’s a feisty 16-year old. She loves being here, she loves being able to fly, she loves having powers. […] She really wants to join up with Superman and help him whenever she can […but] he’s very protective of her because he doesn’t want her rushing into some battle with a supervillain and getting killed. He wants her to realize there’s responsibility involved in what she’s doing.
– Paul Dini, circa 1998 (source: The Justice League Watchtower: Supergirl Bio)
The show made one significant change to the comics canon that was quite refreshing. In the Silver Age origin story, Kara’s father Zor-El is a brilliant scientist like his brother, and creates a spacecraft for his daughter based on Jor-El’s designs. Zor-El leads the effort to save Argo City by constructing a forcefield around the planetoid. The animated series portrays Kara’s mother as a scientist and the one who saved Kara’s life by devising the plan for constructing a forcefield around Argos and building cryochambers for her family. Kara In-Ze is named after her mother, who in the comics was named Alura In-Ze before she married. This revision would later influence her comics reboot, which revealed Alura to be a brilliant scientist who was shown building Kara’s spaceship in Supergirl #24, 2008.
- World’s Finest: Superman:TAS Supergirl Bio and JLU Supergirl Bio – both feature a very nice gallery of high quality images
- The Justice League Watchtower: Supergirl Bio