At the membership drive, Tomorrow Woman is the last to arrive and impresses the Justice League with her formidable telekinetic powers as well as her kind, earnest, and altruistic nature. After passing their tests and fooling their equipment, as well as the telepathy of Martian Manhunter, she is accepted into the team. For the next few weeks, Tomorrow Woman primarily helps the Justice League against a strange menace called IF, which turns out to be a weapon from the future. The League realizes an electromagnetic pulse can deactivate IF and prevent it from causing more destruction. Tomorrow Woman's programming to kill the League activates, but she resists it, telling Green Lantern (Kyle Rayner) that she believes something inside her is bad but that she will choose to act as a hero. She then sacrifices herself, using the EMP weapon to destroy IF and herself. While Ivo is furious at this development, Morrow reveals he deliberately made Tomorrow Woman's brain advanced enough to develop her own personality and ethics, and so her act of free will is an example of his genius and proof that he is better at creating artificial life than Ivo is. Realizing Tomorrow Woman's true nature, the League tracks down and captures Ivo and Morrow. Later, Superman oversees Tomorrow Woman's burial, stating that she was a living woman and not simply a robot.