Although she initially forbids Diana to be trained as a warrior, Hippolyta reluctantly agrees to let General Antiope, Hippolyta's sister and Diana's aunt, train her, only more rigorously than any other warrior. In 1918, Diana, now a young woman, rescues US pilot Captain Steve Trevor when his plane crashes off the Themysciran coast. The island is soon invaded by German soldiers that had been pursuing Trevor. The Amazons kill the crew, but Antiope sacrifices herself to save Diana. Steve is interrogated with the Lasso of Hestia and reveals that a great war is consuming the outside world and that he is an Allied spy. He has stolen a notebook of the chief chemist Dr. Isabel Maru, who is attempting to engineer a deadlier form of mustard gas under the orders of General Erich Ludendorff from a weapon facility in the Ottoman Empire. Believing Ares to be responsible for the war, Diana arms herself with the "Godkiller" sword, the lasso, and armor before leaving Themyscira with Steve to locate and stop Ares for good.
"Honestly... I think we're gonna be dead way before that. And you know what? I don't mind. It's an honorable end. But we've gotta shut Steppenwolf down. Superman's a no-show. You've got no powers, no offense. This guy might be working for the enemy. We don't now. You're tripping over your feet, and mine... whuf, you're gorgeous, and fierce... and strong. I know we went to war with the Amazons, but that was before my time. You know what? I don't wanna die. I'm young. There's shit that I wanna do. I just feel like... I didn't really embrace the sea or the land. I've been a loner my whole life. But being part of something bigger, like this... maybe I'm scared because... I'm meant to..."