[SPOILERS for those not caught up on Supergirl ahead.]
Even before it became part of The CW's weekly DC superhero TV show lineup, Supergirl was a series more than happy to embrace the long history of the Superman Family characters in popular media.The show has since alluded to the classic Christopher Reeve movies in season 2, after having cast actors Dean Cain, Helen Slater, Lynda Carter and other noteworthy ex-superhero movie/TV show stars in prominent supporting roles.
Supergirl has also been quite eager to dredge up classic Superman villains, in order to flesh out its enemies roster and add new threats. Now, it sounds possible that another famous Superman/Supergirl baddie will be appearing on the show - and may be played by a familiar face in the history of Superman popular media, no less.
One of Supergirl's longest-running sub-plot threads concerns the fate of Kara's adopted father Jeremiah Danvers, played by the aforementioned Cain. Initially believed dead, he was then revealed to actually be a prisoner of the mysterious alien-hating mad-scientist collective Project Cadmus. Supergirl has since affirmed to her adopted DEO Agent sister Alex that she (and Superman) are working to find him - even after Cadmus' sinister leader implied that he may have been "changed" in some sinister way, in the season 2 episode 'The Last Children of Krypton'.
Supergirl executive producer Andrew Kreisberg, when he spoke to EW, indicated that said "change" may indeed coincide with one popular fan-theory about Jeremiah Danvers' ultimate fate:
“We want to keep the mystery of who and what Jeremiah is alive. He’s been under Cadmus’ control for the last 12 years. The Jeremiah that we see might not be exactly what people expect.”
The report also makes it a point to remind fans than Cadmus' modus-operandi so far has involved using technology to augment humans into anti-alien bioweapons like the season 2 nemesis, Metallo. The implication, especially for longtime Superman fans, would thus appear to be that Cain - best known for playing Superman in the 1990s TV series Lois & Clark - may become not simply another run-of-the-mill villain. Rather, he may be The CW's version of the fearsome "Cyborg Superman"; one of DC Comics' most powerful supervillains.
Debuting as part of the post-Death of Superman storyline "Reign of the Supermen" as one of multiple impostors claiming to be the original Kal-El back from the dead (in this case, the villain claimed to be a mechanically-repaired Superman), Cyborg Superman was actually onetime nemesis Hank Henshaw: a scientist turned evil cyborg who rebuilt himself in Superman's image to destroy his posthumous legacy. If Jeremiah Danvers were to take on some variation of the character's "Terminator meets Superman" appearance, it would compliment an earlier Supergirl fake-out that had now-revealed Martian Manhunter to be using "Hank Henshaw" as his civilian disguise.
Supergirl continues with “Welcome to Earth” on on Monday, October 24 @8PM ET on The CW.