Warning: The following contains SPOILERS for Earth-Prime: Batwoman #1 and Supergirl season 6.

The first issue of the Earth-Prime mini-series confirmed just when in the Arrowverse timeline Supergirl season 6 takes place. This was a point of confusion for many, given all of the usual events which synched up the television shows making up the shared universe of the CW superheroes were canceled in the wake of the COVID-19 pandemic. Thankfully, a conversation between Lena Luthor and Ryan Wilder in Earth-Prime: Batwoman #1 confirmed when the events of Supergirl season 6 occurred and also offered a sample of the crossovers that couldn't be filmed over the past two years.

The action of Earth-Prime: Batwoman (by Natalie Abrams, Kelly Larson, Clayton Henry, and Marcelo Maiolo) was set in the middle of Batwoman season 3, as Ryan Wilder found herself under fire on multiple fronts. Beyond being blackmailed by former GCPD Detective Renee Montoya and threatened by business magnate Jada Jet, Ryan had also just been forced out of her position as CEO of Wayne Enterprises in favor of her half-brother, Marquis Jet. To add insult to injury, this last action had been facilitated, in part, by her best friend, Dr. Mary Hamilton, who had become possessed by Poison Ivy.

Related: Batwing's Forgotten Romance Is Finally Explained in Batwoman Continuity

Given the stress she was under, it was unsurprising that Ryan forgot that she had an appointment with Lena Luthor. The supergenius scientist turned sorceress from Supergirl had officially come to Gotham City to discuss acquiring a sample of Victor Fries' technology for a new renewable energy source. Unofficially she had come to deliver a message from Supergirl regarding the first Batwoman Kate Kane speaking well of Ryan and her hope their two teams could help one another to help more people. The fact that Lena referred to herself as the head of the Lena Luthor Foundation rather than LuthorCorp confirmed that the series finale of Supergirl, where Lena changed the name and focus of her family's company, took place before the events of Earth-Prime: Batwoman #1, which was set just after Batwoman season 3, episode 7, "Pick Your Poison."

Arrowverse Earth Prime Batwoman Lena Luthor Meets Ryan Wilder

Teaming Lena Luthor and Ryan Wilder proves to be a brilliant idea and it is unfortunate that the story of Earth-Prime: Batwoman #1 did not get filmed for the television series. Beyond offering her scientific skills in helping Ryan battle a new incarnation of Clayface, Lena also gives Ryan some advice on handling both Jada and Marquis Jet, having had ample experience working around both her own manipulative mother and her megalomaniac brother, Lex Luthor. Lena also tells Ryan that Kate Kane spoke well of her to Kara Danvers and thought the two of them "could make a pretty fine team someday."

Sadly, fans of Supergirl will never get to see that particular World's Finest team-up, unless Melissa Benoist returns to play Kara Danvers one more time in a future episode of Batwoman. This presumes, of course, that there are future episodes of Batwoman, as the series has yet to be renewed for season 4. Fans can rest easy, however, knowing now just when the final episodes of Supergirl took place relative to the rest of the Arrowverse series.

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