After defeating Giganta in battle, Wonder Woman was approached by a lawyer who informed her that she had inherited the estate of Hercules, who had been killed. Shortly thereafter, she was told by A.R.G.U.S. that Hercules' body came from an area containing traces of energy unique to Apokolips. Diana visited Hercules' home and found a letter addressed to her, informing her of the location of her twin brother, Jason. She found him in Greece, and the two seemingly began to bond, only for Jason to turn against Diana after the arrival of Grail, who he had secretly allied himself with. Grail had begun killing children of the earthly gods in order to use their divine power to restore her father Darkseid to adulthood, as he had been turned into a baby at the end of the Darkseid War. Jason allied himself with her in order to exact revenge on Wonder Woman, as he resented her for not seeking him out after she learned of his existence some time ago and was envious of her. However, as Darkseid was about to drain Diana's life force, Jason regretted his actions and joined Wonder Woman in battle against Grail and Darkseid. Then, Hercules' lawyer revealed his true identity as the King of the Gods himself, Zeus. Zeus fought Darkseid while Wonder Woman took on his daughter, Grail. Ultimately, Zeus was defeated and his life force was drained by Darkseid, restoring the Apokoliptian to his full adult form. The Justice League arrived, forcing Darkseid and Grail to retreat through a Boom Tube. In the aftermath of the battle, Diana forgave her brother for his deceit.
In London, they deliver Maru's notebook to the Supreme War Council, where Sir Patrick Morgan is trying to negotiate an armistice with Germany. Diana translates Maru's notes and reveals that the Germans plan to release the deadly gas at the Western Front. Although forbidden by his commander to act, Steve, with secret funding from Morgan, recruits spy Sameer, marksman Charlie, and smuggler Chief Napi to help prevent the gas from being released. The team reaches the front in Belgium. Diana goes alone through No Man's Land and captures the enemy trench, allowing the Allied forces to help her liberate the village of Veld. The team briefly celebrates, taking a photograph in the village, while Diana and Steve begin to develop their own romance.
In one episode, a newspaper editor named Brown, desperate to discover Wonder Woman’s past, assigns a team of reporters to chase her down; she easily escapes them. Brown, gone half mad, is committed to a hospital. Wonder Woman disguises herself as a nurse and brings him a scroll. “This parchment seems to be the history of that girl you call ‘Wonder Woman’!” she tells him. “A strange, veiled woman left it with me.” Brown leaps out of bed and races back to the city desk, where he cries out, parchment in hand, “Stop the presses! I’ve got the history of Wonder Woman!” But Wonder Woman’s secret history isn’t written on parchment. Instead, it lies buried in boxes and cabinets and drawers, in thousands of documents, housed in libraries, archives and collections spread all over the United States, including the private papers of creator Marston—papers that, before I saw them, had never before been seen by anyone outside of Marston’s family.