In this volume, Supergirl makes her debut in the series. When a frightened Kara Zor-El tears up the city, Superman and Batman work to stop her. When they do, they realize she's Superman's cousin. Superman decides to keep her at the Fortress.
With Batman not liking the idea of Superman keeping her, they're realationship breaks appart. Meanwhile, on Apokolips, Granny Goodness is training the newest recruit to be a Female Fury. While in battle with them, "Precious" is easily torn apart. Darkseid tells Granny about the girl who fell to Earth, and orders her to retrieve her. On an outing in Metropolis, Kara and Clark run into an unexpected visitor, Wonder Woman.
Wonder Woman takes the young Kara to Themyscira to train. It is here that Superman shows how protective he is when he almost kills Artemis. It isn't long after the island is attacked by an army of Doomsdays. Then it is revealed to be just a distraction while the Furys take away Kara.
Realizing they'd need more help, Superman, Batman, and Wonder Woman go to the house of Scott Free. It is here that Barda decides to join the team to get back Kara. On Apokolips they all split up. Superman eventually finds Kara, but is shocked to learn she joined Darkseid.
Given the order, Kara attacks Superman. Realizing there is only one way out of this, Superman pulls a ring from his lead lined belt. A ring with it's jewel being a chunk of Krypton is what he pulled out. With one punch, he had Kara down. He then takes the girl home.
When they got back, Superman named Kara, Supergirl. It wasn't long till Darkseid decided he needed Kara back. In a long battle, Superman finally defeats Darkseid by trapping him in the Source Wall. Supergirl is then welcomed to the JLA.