In Superman: The Animated Series, Supergirl was introduced as Kara In-Ze, from Krypton's "sister world" of Argo. A headstrong and independent teenage girl, she was placed in suspended animation before Argo became uninhabitably cold due to the aftershocks of Krypton's destruction, and later found by Superman. The Kents—Clark Kent's adoptive parents—took Kara in, with her posing as Clark's cousin Kara Kent. This Supergirl shares Superman's vulnerability to kryptonite; she also suffers from cheimatophobia (fear of cold) due to the events leading up to her time in suspended animation.
This Supergirl currently appears in the USA on Cartoon Network's Justice League Unlimited animated television series. On that show, Cadmus creates a clone of Supergirl named Galatea for nefarious purposes. Grown into a slightly more mature physical state, the clone resembles Power Girl. Both Supergirl and Galatea were voiced by Nicholle Tom. At the start of Justice League Unlimited's third season, Supergirl undergoes a costume change to one that more closely resembles the new comics Kara Zor-El. In the series, she has a rivalry with Stargirl; this is an odd contrast to the Supergirl comic book series, where Stargirl and Supergirl are friends.
In the fifth season episode, Far From Home, Supergirl travels with the Green Lantern and Green Arrow into the 31st century in order to aid the Legion of Super-Heroes against the Fatal Five. Falling in love with Brainiac 5, who tells her that historical records show that she never returns to the past, and who believes that she will die, Supergirl proves her worth by single-handedly defeating almost the entire mind-controlled Legion. At the episode's conclusion, she proves history true by electing to stay in the future with Brainiac.
Live-action television
A girl named Kara (played by Adrianne Palicki) appears in an episode of the Smallville television series claiming to be from Krypton in the episode "Covenant". This Kara did not claim to be Kal-El's cousin, though, and she seemed to be interested in him in a sexual way. At night, she emerges from the woods naked and uses her strength to ruin a car. Acquiring clothing (but not footwear), she goes to Clark Kent's house. It is later revealed that she was not an actual Kryptonian, but an innocent girl kidnapped, brainwashed, and given superpowers by the artificial intelligence that claims to be based on the mind of Jor-El. She was recruited by the A.I. to bring the teenage Clark Kent to confront his Kryptonian heritage and to persuade him to follow his destiny, which is as yet not disclosed. She took Clark Kent to an ancient Indian cave which contains Kryptonian technology. In the end she vanishes, "Jor-El" saying she'd "served her purpose". It is not known whether she survived this or whether she will ever return in the series.
The human name that Kara had in Smallville was not Linda Lee Danvers, but Lindsey Harrison, who was reported missing after the 1988 meteor showers of Smallville. The car that she and her mother (who was driving) was found on Route 8, which was near the Kawatche Caves. According to Jonathan Kent, Jor-El kidnapped her body, and kept Harrison in stasis, for 16 years.