When it comes to the TV side of the DC Multiverse, Arrow's Stephen Amell has (lately) seemed to get the short-shrift in terms of publicity and critical appreciation. But while his character's titular series may not have Supergirl's topical bonafides or Flash's universe-expanding inventiveness, what Arrow does have is Amell himself: a preternaturally gifted charmer who's expanded his own brand by becoming a charismatic press favorite and even nudging his way into a WWE professional-wrestling storyline.
The next target for superhero television's most enthusiastic self-promoter? A Supergirl guest-spot, naturally.
Speaking to IGN for a comprehensive interview, the ever-amiable Arrow star was asked about the place of his "normal" human hero in an expanding DC continuity that now features (among other things) human/animal hybrids, speed-force users, time travel, animal-spirit avatars and a multiverse of alternate Earths. The topic inevitably turned to fellow CW "Arrowverse" star Grant Gustin's upcoming crossover with CBS' Supergirl. Said Amell of a potential Arrow/Supergirl crossover:
"Sure! In this iteration of the DC Universe, the "Television Universe" as it were, I'm the guy that's been around the longest, so I always feel -- whether I'm on a show or I'm not on a show -- I always feel as though I can in some way, shape or form represent them, and I always want them to be wildly successful and last for many more years than we end up lasting, because I just want to see people have success. So I would love to go over to Supergirl. That would be a blast, if for no other reason than I miss shooting in Los Angeles."
As established (briefly) in recent episodes of The Flash and expected to be confirmed by the upcoming crossover; Arrow, Flash and DC's Legends of Tomorrow take place in a similar but alternate dimension from Supergirl - a variation on the multiverse or "Infinite Earths" concept that has been an organizing principal of the DC Comics Universe off and on since the Silver Age. Originally introduced in the pages of The Flash, the idea of a parallel Earth 2 was originally established to explain why certain DC superhero-identities had been rebooted in the early 1960s while others had continued their stories reaching back to the post-WWII era. It later expanded to encompass home-dimensions for characters acquired from defunct rival publishers and alternate versions of popular characters; such as a world where the heroes were evil and analogs to Lex Luthor and The Joker were good guys.
It's unclear exactly what mechanism would land Amell's Oliver Queen in Supergirl's universe as, unlike The Flash, Green Arrow typically does not have regular access to interdimensional travel. An aged Queen has now appeared as part of Legends of Tomorrow, but that instance involved time-travel within his own universe - a different animal entirely. Still, if the Supergirl/Flash crossover goes over well with fans, look for the topic of a Supergirl/Arrow crossover to at least be raised again by the shows' cast and/or crew alike.
The Flash returns with ‘Trajectory’ on March 22nd @8pm on The CW. Arrow returns with ‘Broken Hearts on March 23rd @8pm on The CW. Legends of Tomorrow will return with ‘Marooned’ on March 3rd, 2016 at 8pm on The CW. Supergirl will return with “Solitude” next Monday @8pm on CBS.