Crisis on Infinite Earths: Part One - S5-E9
Trivia: One question Marv Wolfman continues to get asked at fan conventions is why he killed Kara off in the "Crisis" comics. With so many characters established as having survived Krypton's destruction - including Clark, Kara, Krypto the Superdog, criminals banished to the Phantom Zone, and the bottled Kandor - his goal was to make Superman unique as the planet's sole survivor; killing Kara gave him the creative freedom to return Clark to his origin as the Last Son of Krypton.
Answer: Yes, s02e22. As Kara leaves her office, she said "go get them, Supergirl" to herself. After season 1, the show switched from a CBS production to a CW production and filming moved from L.A. to Vancouver. Flockhart isn't really a fan of traveling to shoot, and didn't want to be away from her family for so long.
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