Since the start of The Flash, actor Tom Cavanagh has embarked on a series of new iterations of Harrison Wells, a brilliant scientist whose fate was intertwined with that of The Flash (Grant Gustin). In the show's first season, it was revealed that the Wells all of the heroes knew was in fact an imposter -- Eobard Thawne, the Reverse Flash, had killed Wells and taken his place in history in order to hasten the accident that made Barry Allen into The Flash. In later seasons, after the multiverse was incorporated into the show, Cavanagh played various different versions of Wells from throughout time and space.
During an interview with Fake Doctors, Real Friends -- a Scrubs rewatch podcast hosted by series stars Zach Braff and Donald Faison, Cavanagh was quizzed on the ramifications of the Crisis on Infinite Earths. Following the end of the multiverse as we knew it, Faison asked, does that mean that Nash Wells/Pariah is in fact the last living version of the character, and that Cavanagh is finished jumping from body to body each season?
"Here's what's ridiculous about doing a superhero comic show -- I run into people like you and I'm just so inferior with my knowledge," Cavanagh told Faison. "You know more than me. I'm not exaggerating, I'm not trying to play dumb. I understand by listening to you that you have a better grasp of the whole thing than I do. I feel like -- as you guys know when you do a long-running television show -- if there needs to be another Wells, there can be another Wells."
Of course, there's at least one more -- kind of. In the final few episodes of the season which was cut short by the coronavirus pandemic, The Flash began slowly reintroducing Eobard Thawne, positioning him to be a major antagonist for the first time since "Crisis on Earth-X." While Thawne typically appears in some form or another during each season of The Flash, the speedster villain's most memorable story was in the show's first season, and sinec then his role has been comparably minor.
Following the events of the Crisis, "Nash" Wells -- who had been manipulated into being a part of the Anti-Monitor's plan to wipe out existence -- began to see what he believed to be guilt-induced hallucinations of other versions of Wells from throughout the multiverse. Ultimately the alternate versions started to fade away and only Thawne remained -- although the villain never made his big move before the series had to go on hiatus.
The Flash (and Nash Wells, and Eobard Thawne) will return to The CW in January 2021.