After a training session, Diana happened to come across Captain Steve Trevor during his escape from the Imperial German Army. A battle soon followed, as the Germans tracked Trevor to Themyscira, where they invaded in pursuit of Doctor Poison's notes. The loss of her aunt and realization of Mankind's downfall during the absence of the amazons convinced Diana to join the war effort, recognizing Ares as the instigator of the conflict.
Hermes attacked Wonder Woman there, refusing to simply give up the child, but during their battle, War ripped the baby from Demeter's womb and disappeared. Unable to let a grave wound such as that go unattended, Diana saw to Demeter first, and the goddess warned that War could not be trusted. Worriedly, Diana and Orion returned to Manhattan to find that War had returned the baby to Zola. At last, the baby and his mother were reunited - and Orion would not have to look any further for the child he needed to kill.