Warning: The following contains SPOILERS for Black Lightning, season 3, episode 14, “The Book Of War: Chapter 1: Homecoming”

The latest episode of Black Lightning just changed the history of the Arrowverse in a big way, revealing the secret role the US Army played in creating the first metahuman in recorded history. This would be a big deal even without the implications it suggests regarding how drastically history has been altered on Earth-Prime following Crisis on Infinite Earths.

The story of Black Lightning focused upon the city of Freeland, Georgia, and how it became a breeding ground for metahumans under the watchful eye of the American Security Agency (ASA); first as the site of a government vaccination program meant to turn urban youths into metahumans in the 1980s and then through the release of a street drug called Green Light that accomplished the same ends in 2018. One ongoing subplot of the series involved a briefcase owned by ASA agent Martin Proctor, which contained important information regarding the ASA’s operations in Freeland. “The Book Of War: Chapter 1: Homecoming” saw Proctor’s briefcase coming into the possession of Black Lightning’s ally and foster father Peter Gambi.

In the final scene of “The Book Of War: Chapter 1: Homecoming,” Gambi revealed what he had learned from the briefcase and how it detailed the secret history of metahumans in America. Gambi discovered that scientists working for the US Army began conducting experiments to create genetically enhanced super-soldiers during World War II. Every test subject taking part in the experiment died except for one man - a soldier named Tyson Sykes, who developed enhanced strength and agility, a slowed rate of aging, and the telepathic ability to impose his will onto others. This was because Sykes was the only test-subject who had the metagene, a rare genetic marker that would trigger accelerated evolution in a subject, allowing it to survive extreme trauma. Given the codename Gravedigger, Sykes became a secret weapon for the US Army and the first metahuman in recorded history.

This revelation immediately raises questions regarding the status of the Justice Society of America in Earth Prime’s past. First revealed to exist on Earth-1 in the season 1 finale of Legends of Tomorrow, the JSA were a group of special individuals recruited by the United States government in 1942 to fight the Nazi menace in secret. The JSA disbanded in 1956, shortly after recovering a reality-altering artifact known as the Spear of Destiny, which they broke into multiple pieces and scattered across time so that it could never be used again. The hunt for the Spear and the battle with the Legion of Doom who sought to rebuild it informed the central plot of Legends of Tomorrow season 2.

While these two histories might seem incompatible at first glance, they are not wholly irreconcilable, though it is possible that the JSA simply never existed on Earth-Prime. It seems likely, however, that the program that created Gravedigger might have been inspired by the existence of the JSA and certain elements in the US government wishing to create a more controllable source of enhanced individuals. The existence of Gravedigger and the JSA may have also fueled the Japanese government’s creation of Mirakuru - a formula intended to create super-soldiers, which led to Slade Wilson’s transformation into Deathstroke in the Arrowverse.

It seems unlikely that Black Lightning or any of the other Arrowverse series will fully explore this secret history anytime soon. With the JSA primed to be reborn on Earth-2 as part of the upcoming Stargirl series, there seems little reason to muddy the waters and risk further confusion by reintroducing another version of the team so soon after Crisis on Infinite Earths. In any case, the idea that the American government has been aware of the existence of metahumans and trying to create them long before the STAR Labs’ particle accelerator explosion will doubtlessly have major repercussions on the future of the Arrowverse.

Next: How The Arrowverse Can Pay Off Crisis’ Wonder Twins Easter Egg