When Supergirl saves a terminal boy, she tells him he'll be alright now. The child takes this as he is not going to die within weeks. Supergirl visits him in the hospital to set things right. At the last moment, she tells him that he is going to live and she won't let him die. Everyone in the room, including Superman freezes as a man in armor appears and shoots at Kara with a Kryptonite gun. He then teleports Supergirl into the future.
The machine that was used to bring here there was destroyed and the man that kidnapped her is the only one that can fix it. He is marked for death but Supergirl flies him out of there to get answers. He tells here that because of her, they are no longer humans. The man ingests poison that will kill him and prevent Supergirl from returning to her time to save the boy.
Supergirl flies the man back to where the machine is so he can fix it before he dies. They find the machine has already been repaired. The man is saddened by the appearance of the Batmen.
One of the Batmen approaches Kara and tells her it's "been a while." She asks if he's Bruce and he replies, "Sort of." They send her back to her time. The dying man begs her not to save the boy. She asks one of the Batmen what she should do. He tells her to forget the man and to say hello to Clark.