With an adaptation of “Flash of Two Worlds,” The Flash season 7 can set up Jay Garrick’s Stargirl crossover. John Wesley Shipp’s Jay Garrick has been missing from the Arrowverse for a while now, with his last appearance being in a pre-Crisis season 6 episode of The Flash. However, the character is confirmed to return in both The Flash and Stargirl.

The current whereabouts of Jay Garrick have been a mystery ever since the Crisis happened. It was at first unclear if he survived the destruction and subsequent rebirth of the multiverse, but it was stated that Jay is alive in the Arrowverse, and will return to The Flash. Exactly when that will happen was finally revealed in the promo for The Flash’s 150th episode, which is the first half of The Flash’s two-part season 7 finale. The promo previewed a team-up between Barry Allen (Grant Gustin), Jay Garrick, Nora West-Allen (Jessica Parker Kennedy), and Bart Allen (Jordan Fisher), who will apparently work together in an attempt to stop a The Flash's pending Godspeed civil war.

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Regardless of what transpires in the season 7 finale, the 150th episode won’t be the last viewers will see of John Wesley Shipp’s speedster hero. It was announced months ago by The CW that Jay Garrick will appear in a flashback-heavy episode of Stargirl season 2. The world of Stargirl was shown to be one of the new Earths created by the ending of “Crisis on Infinite Earths” even though its story feels like it’s far-removed the Arrowverse. That may be about to change since Stargirl has moved from DC Universe to The CW. Jay Garrick’s inclusion is an indication of that as well, given that his arrival will give Stargirl its first-ever Arrowverse crossover. As for how it will work, it’s possible that The Flash season 7 will set it in motion with a “Flash of Two Worlds”-inspired story.

Flash of Two Worlds In DC Comics Explained

Barry and Jay running towards a victim in Flash Of Two Worlds

During the Golden Age, Jay Garrick was DC Comics’ Flash. As it moved on to Barry Allen in the 1950s, Garrick was slowly forgotten. Later, he was revived for a standalone story in The Flash #123, published in 1961. In the comic, Barry Allen accidentally used his speed to run to Earth-2 for the first time. While there, it was established that Jay Garrick’s DC Comics adventures didn’t happen on Barry’s world. In the eyes of people like Barry, Jay was a comic book character, as opposed to a real-life superhero. Barry had quite the shocking realization when he encountered Jay, who had actually retired from crime-fighting some time ago. Jay’s intention was to put his days as the Flash behind him, but the return of three villains from his Golden Age rogues’ gallery forced him into a team-up with Barry. Together, the two Flashes beat the villains and saved the day. In the aftermath of the fight, Jay concluded that he had given up on being a costumed hero too soon. As a result, Jay Garrick resumed his role as Earth-2’s Flash and has maintained a presence in the DC Universe ever since.

Post-Crisis Jay Garrick May Be A Retired Flash (But From Which Earth?)

The team-up in The Flash #123 can be brought to life in the Arrowverse via Jay Garrick’s return, especially if the show reboots his character. A big change may be necessary, since his home, Earth-3, was wiped out by the Crisis. Jay residing on Earth-Prime is plausible, but it would come with problems. First of all, Jay is a doppelgänger of Barry’s father, so it’s not clear if he can be a part of its history (even though Henry Allen is dead). Also, there’s the issue of both Jay and Barry being known as The Flash. The Arrowverse may prefer to avoid Earth-Prime having two Flashes. One solution to this is to reveal that Jay is Earth-Prime’s retired Flash. It could be that in the rewritten version of the Arrowverse’s history, Barry Allen is actually using the mantle of a forgotten superhero. Jay could have walked away from the superhero life decades ago to live a quiet life with his wife, Joan Williams (Michelle Harrison), and perhaps even raise a family.

This could be the direction The Flash takes with its 150th episode, but it could take an alternative approach if its intention is for Shipp to play just one character on The Flash and Stargirl, rather than two different iterations of Jay Garrick. This would involve a more accurate adaptation of “Flash of Two Worlds.” It may be that post-Crisis Jay is the Justice Society’s Flash from Stargirl’s Earth-2. That Jay was supposedly killed by the Injustice Society, but he wouldn’t be the first member to turn up alive. After all, it was discovered that Starman isn’t dead in the Stargirl season 1 finale.

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How The Flash Season 7 Can Set Up Jay Garrick's Stargirl Role

In a reversal of “Flash of Two Worlds,” Jay can leave Earth-2 to visit Barry in Central City, instead of vice versa. Team Flash doesn’t know about the existence of the other Earths in the new Arrowverse multiverse yet, but this discovery could be made very soon. Possibly to investigate resurfaced memories of his past life, the post-Crisis Jay Garrick finds a way to Earth-Prime, thus leading to his alliance with the Allen family against the Godspeed clones. It may be that he doesn’t at first have an interest in suiting up as a superhero, but the circumstances could force his hand. If Barry, Nora, Bart, and the rest of Team Flash can’t win without a fourth speedster, Jay could suit up and go into action. Seeing Jay as a rusty, or perhaps even reluctant superhero would certainly make for an interesting reinvention of the Arrowverse character.

If the Arrowverse tells this story in The Flash season 7, it can provide the setup needed for Jay Garrick’s Stargirl role. As mentioned above, post-Crisis Jay may have hung up his costume after the Justice Society fell apart. If so, he could have been in hiding for the past several years, but fighting alongside the Flash and his allies could inspire him to end his retirement. He could even feel some degree of guilt for staying hidden for so long, which would add one more layer of depth to John Wesley Shipp’s Crimson Comet. Following the team-up, he may determine that when he gets back to Earth-2, he’ll step out of the shadows and help rebuild the Justice Society. There’s also a chance he might find a young speedster that he could train to eventually take his place.

More: The Flash Chose The Wrong Story To Test Its Post-Crisis Formula