Only a few episodes into the series run, Superman has been mentioned during each, but it looks like we'll be getting at least an all-CGI glimpse of the Man of Steel, as seen in this GlobalTV promo for this coming Monday's episode.
It's been unclear whether Superman would have more than a "let's mention Superman because he's been doing the hero thing in this world for longer than you" presence, but apparently that question is being answered here. It looks like he just steps in to temporarily save Kara in her nascent career before letting her then take matters back into her own hands, and hopefully that's the case.
Still, hey! It's Superman on TV for the first time since Smallville, so that's fun for superfans.
Supergirl airs Mondays at 8pm on CBS.