With several main characters already cast, CBS' Supergirl has added two more actors that many superhero fans will surely get a kick out of. Helen Slater, who played Kara Zor-El in the 1984 Supergirl movie, and Dean Cain, who portrayed Superman in the 1990s TV series Lois & Clark: The New Adventures of Superman, have joined the DC Comics adventure series, according to a TV Line report. Unfortunately, the site doesn't specify which characters they will be playing.

Helen Slater and Dean Cain join a burgeoning cast that already includes Melissa Benoist as Kara Zor-El, Mehcad Brooks as Kara's neighbor and co-worker Jimmy Olsen, Calista Flockhart as Kara and Jimmy's employer and CatCo founder Cat Grant, Laura Benanti as Kara's Kryptonian birth mother Alura Zor-El, Chyler Leigh as Kara's foster sister Alex Danvers and David Harewood as Hank Henshaw, who, in the DC Comics, eventually becomes Cyborg Superman. Both Helen Slater and Dean Cain have also guest starred on CW's Smallville, playing Superman's Kryptonian mother Lara and the immortal Dr. Curtis Knox, respectively.

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These casting additions are quite similar to CW's The Flash reboot casting John Wesley Shipp, who played the original Flash in the 1990 TV series, as Barry Allen's father. Since we don't know who Helen Slater and Dean Cain are playing quite yet, it's possible they will portray characters from the DC Comics, or completely new characters created for the series, which was created by Greg Berlanti and Ali Adler. The series creators will also serve as executive producers alongside Sarah Schechter.