There are any number of reasons for "Supergirl" viewers to be excited for the show's Season 2 finale. Not only will the episode include the return of fan-favorite characters, including Calista Flockhart's Cat Grant, Lynda Carter's POTUS and Tyler Hoechlin's Superman, it will set up the third season of the Melissa Benoist-led superhero drama.

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In a wide-ranging interview with CBR, executive producer Andrew Kreisberg opened up, ever so slightly, about yet another reason the finale is such a big deal. Promising "a feature film quality finale, with huge guest stars, stunts and visual effects," Kreisberg went on to say viewers "will get a glimpse of the Season 3 villain in the finale, which we’re also excited about."

As for who that villain is, Kreisberg did not elaborate. It's already known that General Zod makes his debut in the episode, so odds are he's not the mystery player the EP is hinting at. The way he phrased his answer -- "we will get a glimpse of the Season 3 villain" -- indicates a new player with perhaps just a cameo appearance. We'll just have to wait until the finale airs Monday, May 22 to find out.

Airing Mondays at 8 p.m. ET/PT on The CW, “Supergirl” stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jeremy Jordan, David Harewood and Chris Wood. The episodes, titled “Alex” and “City of Lost Children,” premiere on May 1 and May 8 respectively.