Superheroes are going big these past few years, with film franchises hitting the box office, and TV programs hitting the small-screen most days in the week.

The latest to join the slew of crime-fighters and vigilantes is Supergirl on CBS, and it has been confirmed by The Hollywood Reporter that Chyler Leigh from "Grey's Anatomy" and David Harewood from "Homeland" are the latest to join the cast.

Leigh will play the role of Alex Danvers, Supergirl's foster sister who is fascinated by Kara's powers, and has developed an obsession with science, which led her to become a doctor.

Meanwhile, Harewood will play the role of Hank Henshaw, a one-time CIA Agent who runs the Department of Extra-Normal Operations, and tracks extraterrestrial threats on the planet. In the comics, Henshaw will become a Cyborg Superman, although it is not yet known if Harewood will be taking on this role in the series.

Huffington Post also confirmed that actress Calista Flockhart will be joining the show. Lockhart, who was best known for "Ally McBeal" is going to play Cat Grant, the former journalist turned "self-made media magnate" and founder of global powerhouse, CatCo. She worked with Clark Kent and Lois Lane in the comic books, but there is no news yet if they will be making appearances in the series.

As for Supergirl herself, the role of Kara Zor-El will be played by "Glee" actress Melissa Benoist. The young Kryptonian, who happens to be cousin to Superman, has kept her powers hidden for most of her life on Earth, but then started to embrace it at the age of 24 - which is where the series will center on.

Benoist has made her mark in Hollywood for her stint in "Glee". She also had guest roles in "Homeland" and "The Good Wife." In film, she was also applauded for her appearance in the Academy Award-winning film, "Whiplash" alongside Miles Teller and JK Simmons.

Behind the scenes, Coming Soon noted that the show will be distributed by Warner Bros. TV and Berlanti Productions, who also produced hit series "Arrow" and "The Flash" on CW.

The pilot episode was penned by "No Ordinary Family" scribe Ali Adler, and "Arrow" and "The Flash" writer Greg Berlanti, who will also executive produce the series alongside Sarah Schecter and Warner Bros. TV.

There is no news yet when the series will air, but it is expected to have its premiere later this year.

Will you be watching "Supergirl" as well, or do you think superheroes are played out in television?