Before starting as major DC Comics superheroes, Melissa Benoist (Supergirl) and Grant Gustin (The Flash) both appeared in the Fox musical drama Glee.
In a couple of the early episodes, it is mentioned that Metropolis was destroyed during one of Superman's fights. This suggests that the Supergirl series takes place in the same universe as the film "Man Of Steel" and the new DC films since Metropolis was destroyed during Superman's fight with General Zod in that film.
Calista Flockhart stars on this show as Cat Grant. When she starred in "Brothers & Sisters" she character was another feline name, "Kitty Walker." On the episode of Supergirl, "Livewire," the villain of the week is hunting Cat and calls out, "Here Kitty, Kitty..."
Jay Jackson plays a newsreader in the show, he is most known for playing the newsreader and reporter Perd Hapley in Parks and Recreation
Kara's foster parents are named Jeremiah and Eliza Danvers, a change from the comics in which the Danvers first names were Fred and Edna.
If you take out the two A's in Kara's name, you get Kr, the element symbol of Krypton, her home planet.
In the pilot episode Superman is never once called by the name Superman or by his alias of Clark Kent. He is only referred to as "My cousin," "him," or "he".
The series takes place in National City (a fictional community). DC Comics, from which Supergirl is a character, was previously known as "National Comics" (amongst other company names).
This is the second time Chyler Leigh has played a character with a name that derives from "Alexander." On "Grey's Anatomy" she played Alexandra ""Lexie" Caroline Grey and on "Supergirl" she plays Alex Danvers.
Just as Stephen Amell (for the title role of Arrow (2012)), 'Grant Gustin' (for _The Flash (2014)_), Melissa Benoist was the very first of a thousand actors to audition for the role of Supergirl.
'Melissa Benoist' is the second _Glee (2009)_ cast member to star a DC comics superhero. Grant Gustin portrays the title character in The Flash (2014).
According to Brandon Routh on Twitter, the "bulletproof coffee" Cat mentions in the third episode was used by writer Andrew Kreisberg after Routh's "obsessive" use of the term. Routh, of course, played the title character in Superman Returns (2006) and stars as The Atom in _Arrow (2012)_ (qv_ and its spin-offs.
As a guest on Ellen: The Ellen DeGeneres Show (2003), Melissa Benoist received from Ellen DeGeneres Superman-themed costumes for each of her dogs.
Glenn Morshower, General Sam Lane, had a role in X-Men: First Class (2011) with Michael Ironside, who played General Lane in Smallville (2001).
Melissa Benoist had an eye injury and wore an eye-patch when she put on the Supergirl outfit for the very first time, describing her look as "kind of embarrassing".
In the comics, the character of Lucy Lane assumed the alter ego of Superwoman (who had a costume bearing a field that simulated Kryptonian powers), and was eventually confronted by Supergirl in the story arc "Who Is Superwoman?".
Laura Benanti, who's portraying Alura Zor-El in the series, is 9 years older than her TV daughter Melissa Benoist.
Kara keeps her name and assumes the surname Danvers after she is adopted. In the comics, however, Kara assumed the full name of "Linda Lee Danvers" after she was adopted.
Winn thinks Kara is a lesbian when she is about to reveal her secret identity as Supergirl. In the comics, the Danvers had the same conclusion before their daughter Linda "comes out" as Supergirl to them.
Chyler Leigh portrayed Dr. Lexie Grey (sister of the title character) who died after an airplane crash in Grey's Anatomy (2005). In this series, she is again the sister of a title character, and is saved by her from perishing in an airplane crash in the Pilot.
In addition to acting, Melissa Benoist, Jeremy Jordan, Chyler Leigh, Mehcad Brooks and David Harewood all can sing. According to Melissa Benoist, the idea of a musical episode became "a kind of a running joke" among the cast due to this.
In the Pilot, when Kara is walking against the bullets, she is seen using red shoelaced boots similar to those of Linda Danvers (Supergirl), the character created by Peter David after Kara had been wiped out of DC continuity.
The Supergirl outfit was designed by Colleen Atwood, who also designed the costumes for Arrow (2012) and The Flash (2014).
Melissa Benoist started reading the New 52 'Supergirl' comics after she started playing the character.